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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2013年第12期14卷 856-866页

作者： Hui liu Ming-hua HE Yu-qi luAN Jia GUO lu-lu liu Department of Civil Engineering Tsinghua University Research Institute of Highway of China Ministry of Transport Institute of Chemical Machinery Zhejiang University

OpenSees is a well-recognized open source platform with high compatibility,and it has a well-developed fiber element method to cope with nonlinear structural *** reinforced polymer(FRP)confined concrete can effectively improve the seismic performance of concrete ***,sophisticated constitutive models for FRP confined concrete are not available in the current version of *** this paper,after reviewing several typical FRP confined concrete constitutive models,a modified constitutive model for FRP confined concrete in circular sections was proposed based on Lam and Teng(2003)’s model with four main modifications including the determination of FRP rupture strain,ultimate condition,envelope shape,and hysteretic *** embed the proposed constitutive model into OpenSees is a practical solution for engineering ***,the secondary development of OpenSees New UserMat was briefly demonstrated and a set of critical steps were depicted in a flow ***,with the numerical implementations of a series of FRP confined concrete members covering a wide range of load cases,FRP confinement types and geometric properties,the utility and accuracy of the proposed model compared with Lam and Teng(2003)’s model and new material secondary development in OpenSees were well validated.

关键词： FRP confined concrete Constitutive model OpenSees User material Secondary development

Containment of high-speed rotating disk fragments

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2012年第9期13卷 665-673页

作者： Hai-jun XUAN lu-lu liu Yi-ming FENG Qing HE Juan-juan LI High-Speed Rotating Machinery Laboratory Institllte of Chemical MachineryFacldly of EngineeringZhejiang UniversityHangzhou 310027China

Disk burst accidents sometimes happen in *** avoid tragic consequences,aeroengine casings must have sufficient containment *** and simulations need to be conducted to study the impact,distortion,and perforation caused by disk burst and which may give important clues to potential failure *** paper presents some containment tests of high-speed rotating disk fragments,in which the original disks were burst into three equal fragments within a predetermined rotating speed *** failure modes of the containment casing varied significantly with the thickness of the containment ***,tearing,tensile fracture,and large plastic stretching deformation occurred in a thin-walled containment casing,while a thick-walled casing could contain disk fragments and withstand large plastic *** simulations were carried out to study the impact process and failure modes *** agreement was found between the results of the simulations and the tests.

关键词： Aeroengine Disk fragments Engine casing Containment capability Numerical simulation

Numerical Analysis of Effect of Water on Explosive Wave Propagation in Tunnels and Surrounding Rock

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Journal of China University of Mining and Technology 2007年第3期17卷 368-371页

作者： XIA Chang-jing SONG Zhen-duo TIAN lu-lu liu Hong-bin WANG lu WU Xiao-fang School of Mechanics ＆ Civil Engineering China University of Mining ＆ Technology Beijing 100083 China

Based on the application of practical engineering,propagation processes of explosive waves in rock with water well and tunnel are simulated by ANSYS/LS-DYNA software. The evolution of damage in rock is presented. The effect of water on the damage of the concrete slab in a tunnel is compared with damage inflicted without water. The numerical simulation illustrates that water plays an important role in the evolution of damage of the concrete slab in a mine tunnel. In the presence of water in the rock the concrete slab is damaged more severely than without water in rock. The effect of water location in the rock is also considered. It is found that the concrete slab in the tunnel shows various degrees of damage as a function of the different locations of water. Attenuation laws of stress waves over time-space in rock with water are also obtained. Numerical results indicate that,under blast loading,there are three zones in the rock: a crushed zone nearby the explosive charge,a damaged zone and an elastic zone. The conclusions of numerical analysis may provide references for blasting designs and structure protection.

关键词： explosive wave numerical simulation concrete slab damage evolution

Will the 2022 compound heatwaveedrought extreme over the Yangtze River Basin become Grey Rhino in the future?

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Advances in Climate Change Research 2024年第3期15卷 547-556页

作者： Ai-Qing FENG Qing-Chen CHAO lu-lu liu Ge GAO Guo-Fu WANG Xue-Jun ZHANG Qi-Guang WANG China Meteorological Administration Key Laboratory for Climate Prediction Studies National Climate CentreBeijing 100081China Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China China Institute of Water Resources and Hydropower Research Beijing 100038China China Meteorological Administration Training Centre China Meteorological AdministrationBeijing 100081China

The increasingly frequent and severe regional-scale compound heatwave-drought extreme events(CHDEs),driven by global warming,present formidable challenges to ecosystems,residential livelihoods,and economic ***,uncertainty persists regarding the future trend of CHDEs and their insights into regional spatiotemporal *** integrating daily meteorological data from observations in 1961-2022 and global climate models(GCMs)based on the Shared Socioeconomic Pathways,the evolution patterns of CHDEs were compared and examined among three sub-catchments of the Yangtze River Basin,and the return periods of CHDE in 2050s and 210Os were *** findings indicate that the climate during the 2022 CHDE period was the warmest and driest recorded in 1961-2022,with precipitation less than 154.5 mm and a mean daily maximum temperature 3.4°C higher than the average of 1981-2010,whereas the char-acteristics in the sub-catchments exhibited temporal and spatial *** July-August 2022,the most notable feature of CHDE was its extremeness since 1961,with return periods of~200-year in upstream,80-year in midstream,and 40-year in downstream,*** 2050,the return periods witnessed 2022 CHDE would likely be reduced by *** towards 2100,under the highest emission scenario of SSP585,it was projected to substantially increase the frequency of CHDEs,with return periods reduced to one-third in the upstream and downstream,as well as halved in the *** findings provide valuable insights into the changing risks associated with forthcoming climate extremes,emphasizing the urgency of addressing these challenges in regional management and sustainable development.

关键词： Compound extreme event Joint return period Drought Heatwave Climate change Yangtze River Basin

Engineering in amino acid-functionalized double-layer heteropolymolybdates:from structural control to catalytic activity

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Rare Metals 2023年第10期42卷 3345-3353页

作者： lu-lu liu Yan-Hu Wang Xin-Yu Xiao Ke-Wei Tong Yue Zhao Chao-Qin Chen Jing Du Peng Yang College of Chemistry and Chemical Engineering Advanced Catalytic Engineering Research Center of the Ministry of EducationHunan UniversityChangsha410082China Testing and Analysis Center Hebei Normal UniversityShijiazhuang050024China

A reexamination of the structural constraints on the amino acid-functionalized heteropolymolybdates has afforded four polyanions,namely the double-layer [(SeO_(3))_(2)Mo_(12)O_(36)(CH_(3)COO)_(3)]^(7-)(1),[(SeO_(3))_(1.3)(HPO_(3))_(0.7)Mo_(12)O_(36)(NH_(3)CH_(2)COO)_(3)]^(4-)(2),[(SeO_(3))_(1.4)(HPO_(3))_(0.6)Mo_(12)O_(36)(LNH_(3)C_(2)H_(3)OHCOO)_(3)]^(4-)(3),and the mono-layer [(SeO_(3))-Mo_6O_(18)(L-NH_(3)C_(2)H_(3)OHCOO)_(3)]^(2-)(4),which were crystallized as the hydrated ammonium salts.

关键词： structural layer double

Imaging of hemorrhagic primary central nervous system lymphoma: A case report

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World Journal of Clinical Cases 2020年第15期8卷 3329-3333页

作者： Ya-Wei Wu Jin Zheng lu-lu liu Jun-Hui Cai Hu Yuan Jing Ye Department of Radiology Clinical Medical College of Yangzhou UniversityNorthern Jiangsu People's HospitalYangzhou 225001Jiangsu ProvinceChina

BACKGROUND A primary central nervous system lymphoma(PCNSL)presenting with massive hemorrhage is a rare occurrence that is difficult to distinguish from a high-grade *** descriptions of the imaging characteristics of such tumors have not yet been ***,we reported a case of a PCNSL with massive hemorrhage by presenting the imaging features of computed tomography(CT)imaging and structural and perfusion magnetic resonance imaging(MRI).CASE SUMMARY A 48-year-old man presented with headache lasting for 10 *** of the brain showed a round,heterogeneous,high-density lesion with surrounding edema in the right temporal *** further diagnosis,a series of MRI examinations of the brain were subsequently performed,and a hemorrhagic lesion with ring-like enhancement was *** whole lesion was relatively hypoperfused on arterial spin labeling *** resection of the lesion and histopathological examination confirmed that the lesion was a diffuse large B-cell lymphoma with massive *** PCNSLs with hemorrhage occur very rarely,and structural and perfusion MRI examinations are requested exceedingly *** case provided insight into some characteristics of a hemorrhagic lymphoma on CT and MRI *** MRI examination may be useful for the differential diagnosis of PCNSLs and other brain tumors.

关键词： Primary central nervous system lymphoma Massive hemorrhage Perfusion Multimodal magnetic resonance imaging Lymphoma Case report

Durability of Alite-calcium Barium Sulphoaluminate Cement

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Journal of Wuhan University of Technology(Materials Science) 2009年第6期24卷 982-985页

作者：芦令超 School of Materials Science and Engineering University of Jinan

The durability of the cement was mainly studied. Under 1.0 MPa of hydraulic pressure for 8 hours, water could penetrate completely through the sample made by portland cement, but could not penetrate through that by alite-barium sulphoaluminate cement. Under the condition of freezing and thawing cycle, the loss ratio of compressive strength of the cement was only about 17.3% at curing 28 d ages, but the loss of portland cement was as high as 29.5%. Alite-calcium barium sulphoaluminate cement also has an excellent resistance to sulfate attack. The coefficients of resistance to sulfate attack of the cement exceeded 1.0. Meanwhile, the composition and microstructure of the hardened paste of alite-calcium barium sulphoaluminate cement were analyzed by XRD and SEM.

关键词： durability cement alite calcium barium sulphoaluminate

Risk factors for progression to acute-on-chronic liver failure during severe acute exacerbation of chronic hepatitis B virus infection

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World Journal of Gastroenterology 2019年第19期25卷 2327-2337页

作者： Ling Yuan Bai-Mei Zeng lu-lu liu Yi Ren Yan-Qing Yang Jun Chu Ying Li Fang-Wan Yang Yi-Huai He Shi-De Lin Department of Infectious Diseases Affiliated Hospital of Zunyi Medical University Department of Gastroenterology Jiangsu Province Hospital Pukou Branch Department of Respiratory Medicine the Fifth People’s Hospital of Chongqing

BACKGROUND Acute exacerbation in patients with chronic hepatitis B virus(HBV) infection results in different severities of liver injury. The risk factors related to progression to hepatic decompensation(HD) and acute-on-chronic liver failure(ACLF) in patients with severe acute exacerbation(SAE) of chronic HBV infection remain *** To identify risk factors related to progression to HD and ACLF in compensated patients with SAE of chronic HBV *** The baseline characteristics of 164 patients with SAE of chronic HBV infection were retrospectively reviewed. Independent risk factors associated with progression to HD and ACLF were identified. The predictive values of our previously established prediction model in patients with acute exacerbation(AE model) and the model for end-stage liver disease(MELD) score in predicting the development of ACLF were *** Among 164 patients with SAE, 83(50.6%) had compensated liver cirrhosis(LC),43 had progression to HD without ACLF, and 29 had progression to ACLF within 28 d after admission. Independent risk factors associated with progression to HD were LC and low alanine aminotransferase. Independent risk factors for progression to ACLF were LC, high MELD score, high aspartate aminotransferase(AST) levels, and low prothrombin activity(PTA). The area under the receiver operating characteristic of the AE model [0.844, 95%confidence interval(CI): 0.779-0.896] was significantly higher than that of MELD score(0.690, 95%CI: 0.613-0.760, P < 0.05) in predicting the development of *** In patients with SAE of chronic HBV infection, LC is an independent risk factor for progression to both HD and ACLF. High MELD score, high AST, and low PTA are associated with progression to ACLF. The AE model is a better predictor of ACLF development in patients with SAE than MELD score.

关键词： Acute-on-chronic liver failure Chronic hepatitis B Hepatic decompensation Liver cirrhosis Risk factors Severe acute exacerbation

Antibiotics and immunotherapy in gastrointestinal tumors: Friend or foe?

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World Journal of Clinical Cases 2019年第11期7卷 1253-1261页

作者： Cong Yan Xiao-Xuan Tu Wei Wu Zhou Tong lu-lu liu Yi Zheng Wei-Qin Jiang Peng Zhao Wei-Jia Fang Hang-Yu Zhang Department of Medical Oncology First Affiliated HospitalSchool of MedicineZhejiang University

The incidence of gastrointestinal (GI) tumors is increasing year by year, and its pathogenesis is closely related to the intestinal flora. At present, the use of antibiotics is very common in the clinic. And cancer patients with low immunity are vulnerable to all sorts of infections, such as respiratory tract infections and urinary tract infections. Moreover, cancer patients easily run into fever and neutropenia induced by myelosuppression. Therefore, antibiotics are used extensively and even overused in many conditions. However, because of the special anatomical location of the gastrointestinal tract, the antibiotic usage will bring changes to the intestinal flora. Besides, with the expanding popularity of immunotherapy, various factors affecting the efficacy of immune checkpoint inhibitors (ICIs) have been extensively explored, including cancer-associated inflammation and the local and systemic factors that lead to immunosuppression. Some biomarkers for ICIs, including the expression of PD-L1, tumor mutation load, and microbiota, also have been investigated, and many studies have confirmed that gut microbiota can affect the efficacy of immunotherapy. But further studies on the influence of antibiotics directly on immunotherapy are rare. In this review, we discuss the relationship between GI tumors and antibiotics, the current status of immunotherapy in GI tumors, and the influence of antibiotics on immunotherapy.

关键词： Antibiotics Immunotherapy Gastrointestinal tumor Microbiota Immune checkpoint inhibitors

Negative Association of Circulating MicroRNA-126 with High-sensitive C-reactive Protein and Vascular Cell Adhesion Molecule-1 in Patients with Coronary Artery Disease Following Percutaneous Coronary Intervention

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Chinese Medical Journal 2016年第23期129卷 2786-2791页

作者： Jun-Nan Wang You-You Yan Zi-Yuan Guo Ya-Juan Jiang lu-lu liu Bin liu Department of Cardiology The Second Hospital of Jilin University Changchun Jilin 130041 China

Background： Percutaneous coronary intervention （PCI） causes endothelial damage, resulting in an inflammatory response with elevation of markers such as high-sensitive C-reactive protein （hs-CRP） and vascular cell adhesion molecule-1（VCAM-1）, which are associated with restenosis after PCI. Evidence suggests that microRNA-126 （miR-126） plays an important role in vascular inflammation, but its correlation with PCl-mediated inflammation has not been investigated. In this study, we investigated the effect of PCI on circulating miR-126 and inflammation markers such as hs-CRP and VCAM-1. Methods： We enrolled 130 patients with coronary artery disease （CAD） in the Second Hospital of Jilin University from October 2015 to December 2015. Among them, 82 patients with CAD, defined as at least one major epicardial vessel with 〉70% stenosis who planned to undergo PCI, were divided into acute coronary syndrome （ACS） group （46 patients） and stable angina （SA） group （36 patients）. Forty-eight patients confirmed by coronary angiography without PCI were used as controls. The plasmas of all patients were collected prior to PCI and at 30 min, 24 h, and 72 h after PCI. The plasma VCAM-1 and hs-CRP were detected by enzyme-linked immunosorbent assay, and the miR-126 was evaluated by quantitative reverse transcription-polymerase chain reaction. Results： Plasma concentrations of hs-CRP and VCAM-I in patients with either ACS （n = 46） or SA （n = 36） were significantly higher than in controls （n = 48）（P 〈 0.01） prior to PCI, and increased further at 24 h and 72 h after PCI, compared with prior PCI. Moreover, VCAM-1 was positively correlated with balloon time and pressure. In contrast, the plasma concentration of miR-126 was significantly lower in patients with CAD than in controls, and further decreased with time post-PCl. A negative correlation was observed between miR-126 and hs-CRP and VCAM-1 at 72 h after PCI. Conclusion： There was a negative correlation of miR-126 with the PCI-induced marke

关键词： High-sensitivity C-reactive Protein MicroRNA126 Percutaneous Coronary Intervention Vascular Cell Adhesion Molecule- 1