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Three new triterpenoids from Rubia schumanniana

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Natural Products and Bioprospecting 2012年第4期2卷 166-169页

作者： Bin KUANG Jing HAN guang-zhi zeng Xiao-Qiang CHEN Wen-Jun HE Ning-Hua TAN State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of BotanyChinese Academy of SciencesKunming 650201China Graduate University of Chinese Academy of Sciences Beijing 100049China

Three new triterpenoids,3β-hydroxy-urs-30-p-Z-hydroxycinnamoyl-12-en-28-oic-acid(1),3β-hydroxy-olean-30-p-E-hydroxycinnamoyl-12-en-28-oic-acid(2)and 3β,6α-dihydroxy-urs-14-en-12-one(3),together with seven known triterpenoids,were isolated from the roots of Rubia *** structures were established by means of spectroscopic *** compounds were evaluated for cytotoxic activity,and compounds 2-6 showed cytotoxicity with the IC50 values of 10.75~18.87μg/mL.

关键词： Rubia schumanniana triterpenoid cytotoxicity

Working condition recognition of sucker rod pumping system based on 4-segment time-frequency signature matrix and deep learning

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Petroleum Science 2024年第1期21卷 641-653页

作者： Yun-Peng He Hai-Bo Cheng Peng zeng Chuan-zhi Zang Qing-Wei Dong guang-Xi Wan Xiao-Ting Dong State Key Laboratory of Robotics Shenyang Institute of AutomationChinese Academy of SciencesShenyang 110016LiaoningChina Key Laboratory of Networked Control Systems Chinese Academy of SciencesShenyang 110016LiaoningChina Institutes for Robotics and Intelligent Manufacturing Chinese Academy of SciencesShenyang 110169LiaoningChina University of Chinese Academy of Sciences Beijing100049China School of Artifcial Intelligence Shenyang University of TechnologyShenyang 110870LiaoningChina

High-precision and real-time diagnosis of sucker rod pumping system(SRPS)is important for quickly mastering oil well *** learning-based method for classifying the dynamometer card(DC)of oil wells is an efficient diagnosis ***,the input of the DC as a two-dimensional image into the deep learning framework suffers from low feature utilization and high computational ***,different SRPSs in an oil field have various system parameters,and the same SRPS generates different DCs at different ***,there is heterogeneity in field data,which can dramatically impair the diagnostic *** solve the above problems,a working condition recognition method based on 4-segment time-frequency signature matrix(4S-TFSM)and deep learning is presented in this ***,the 4-segment time-frequency signature(4S-TFS)method that can reduce the computing power requirements is proposed for feature extraction of DC ***,the 4S-TFSM is constructed by relative normalization and matrix calculation to synthesize the features of multiple data and solve the problem of data ***,a convolutional neural network(CNN),one of the deep learning frameworks,is used to determine the functioning conditions based on the *** on field data verify that the proposed diagnostic method based on 4S-TFSM and CNN(4S-TFSM-CNN)can significantly improve the accuracy of working condition recognition with lower computational *** the best of our knowledge,this is the first work to discuss the effect of data heterogeneity on the working condition recognition performance of SRPS.

关键词： Sucker-rod pumping system Dynamometer card Working condition recognition Deep learning Time-frequency signature Time-frequency signature matrix

Oxyphyllones A and B,novel sesquiterpenes with an unusual 4,5-secoeudesmane skeleton from Alpinia oxyphylla

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Chinese Chemical Letters 2009年第8期20卷 945-948页

作者： Jun Ju Xu Ning Hua Tan Jiang Xiong Abiodun Humphrey Adebayo Hong Jin Han guang zhi zeng Chang Jiu Ji Yu Mei Zhang Mei Ju Zhu State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of BotanyChinese Academy of Sciences Kunming 650204 PR China Department of Biological Sciences College of Science and Technology Covenant University Ota P.M.B. 1023 Ogun State Nigeria Graduate University of the Chinese Academy of Sciences Beijing 100049 PR China

Two novel 4,5-secoeudesmane sesquiterpenoids, oxyphyllones A （1） and B （2） were isolated from the fruits of Alpinia oxyphylla. Their structures were established by spectroscopic methods including 1D and 21） NMR spectra. These two compounds are the first example of naturally occurring sesquiterpenoids with a 4,5-secoeudesmane skeleton in the family of Zingiberaceae and oxyphyllone A （1） is the first 4,5-secoeudesmane type of 13-norsesquiterpenoid. Compounds 1 and 2 exhibited no cytotoxicities against three cancer cell lines at 10 μg/mL. ？ 2009 Ning Hua Tan. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

关键词： Alpinia oxyphylla Zingiberaceae 4,5-Secoeudesmane sesquiterpenoid Oxyphyllone A Oxyphyllone B

Influence of Vanes and Blades on Ingress in Axial Rim Seal for Turbine Stages

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Journal of Thermal Science 2024年第3期33卷 833-846页

作者： REN Ran DU Qiang LIU guang zeng Yanlian XIE Lei Institute of Engineering Thermophysics Chinese Academy of SciencesBeijing100190China National Key Laboratory of Science and Technology on Advanced Light-duty Gas-turbine Beijing100190China School of Aeronautics and Astronautics University of Chinese Academy of SciencesBeijing100190China

Hot gas ingestion refers to the phenomenon of mainstream hot gas flowing into the space cavity of a turbine *** studies have found that mainstream annulus pressure distribution plays an important role in hot gas ingestion,but due to its complexity,the mechanism of the interaction between mainstream flow and hot gas ingestion remains *** paper adopts the URANS method,and three sealing flow rates are considered,named C_(w)=0,C_(w)=500,and C_(w)=*** time-averaged annulus pressure distribution shows that an increase in the sealing flow decreases the pressure value,and the effects of the sealing flow on the pressure distribution of the leading edge of the blade are much more influential than that of the trailing edge of the *** unsteady pressure time-space distribution in the annulus indicates that a time-space tilted distribution of pressure at the rim exits when the sealing flow *** phenomenon is mainly due to the strong feedback mechanism of the sealing flow to the annulus pressure field.A comparison of the pressure and mean radial velocity distribution of the mainstream shows that the ingestion mainly occurs on the blade side,where the pressure is lower than on the vane *** flow characteristics at the wheel rim are analyzed with a sealing flow rate C_(w)=5000,and under these conditions,both pressure-induced ingestion and ingestion caused by a passage vortex can be *** three-dimensional and inertial effects of the mainstream at the wheel rim lead to the generation of separation vortices on the blade side,and the presence of separation vortices leads to ingestion along the blade *** the same time,pressure on the blade side will cause the fluid to have a radial inward flow tendency,which will promote the formation of separation vortices,leading to more serious ingestion in the high-pressure region on the blade *** blade pressure field can be more significant than the vane trailing pressure field in the rim sea

关键词： separation vortex unsteady rim seal the effect of blade on ingestion

Long-term clinical outcomes and health-related quality of life in patients with isolated methylmalonic acidemia after liver transplantation:experience from the largest cohort study in China

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World Journal of Pediatrics 2024年第8期20卷 809-821页

作者： Yi-Zhou Jiang guang-Peng Zhou Lin Wei Wei Qu zhi-Gui zeng Ying Liu Yu-Le Tan Jun Wang zhi-Jun Zhu Li-Ying Sun Department of Critical Liver Diseases Liver Research CenterBeijing Friendship HospitalCapital Medical UniversityNo.101 Lu Yuan Dong RoadTong-Zhou DistrictBeijing110112China Liver Transplantation Center National Clinical Research Center for Digestive DiseasesBeijing Friendship HospitalCapital Medical UniversityBeijingChina Clinical Center for Pediatric Liver Transplantation No.101 Lu Yuan Dong RoadTong-Zhou DistrictCapital Medical UniversityBeijing110112China

Background Liver transplantation(LT)has been proposed as a viable treatment option for selected methylmalonic acidemia(MMA)***,there are still controversies regarding the therapeutic value of LT for *** systematic assessment of health-related quality of life(HRQoL)-targeted MMA children before and after LT is also *** study aimed to comprehensively assess the long-term impact of LT on MMA,including multiorgan sequelae and HRQoL in children and *** We retrospectively evaluated 15 isolated MMA patients undergoing LT at our institution between June 2013 and March ***-and post-transplant data were compared,including metabolic profiles,neurologic consequences,growth parameters,and *** further assess the characteristics of the HRQoL outcomes in MMA,we compared the results with those of children with biliary atresia(BA).Results All patients had early onset MMA,and underwent LT at a mean age of 4.3 *** 1.3–8.2 years of follow-up,the patient and graft survival rates were 100%.Metabolic stability was achieved in all patients with liberalized dietary protein *** was a significant overall improvement in height Z scores(P=0.0047),and some preexisting neurological complications remained stable or even improved after *** the Pediatric Quality of Life Inventory(PedsQL™)generic core scales,the mean total,physical health,and psychosocial health scores improved significantly posttransplant(P<0.05).In the family impact module,higher mean scores were noted for all subscales post-LT,especially family function and daily activities(P<0.01).However,the total scores on the generic core scales and transplant module were significantly lower(Cohen’s d=0.57–1.17)when compared with BA *** particular,social and school functioning(Cohen’s d=0.86–1.76),treatment anxiety,and communication(Cohen’s d=0.99–1.81)were far behind,with a large effect *** This large single-center study of the mainland of China sh

关键词： Health-related quality of life.Inborn error of metabolism Isolated methylmalonic acidemia Liver transplantation:Outcomes

Impact wear properties of dissimilar joints between bainitic frogs and pearlite rails

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Journal of Iron and Steel Research International 2024年第1期31卷 275-287页

作者： Pin-yong zeng Chun-guang Zuo Xiao-yu Zhang Wei Li Tribology Research Institute Southwest Jiaotong UniversityChengdu610031SichuanChina

The impact wear behavior and damage mechanism of dissimilar welded joints between U26Mn frog and U75 V rail before and after normalizing treatment were studied by cyclic impact *** experiment indicated that the impact wear volume of the joints increased with the increasing number of impact *** main wear mechanisms include pitting wear,mild fatigue wear,delamination wear,and fatigue wear,and plastic deformation was the primary impact wear *** them,fatigue wear had the greatest influence on wear volume,while other wear mechanisms had limited *** impact wear resistance of the base material was better than that of the heat-affected *** treatment was beneficial to improving the impact wear resistance of welded joints owing to its effect to promote pearlite recovery,grain refinement,and uniform distribution of *** martensite generated in the rail welded joints aggravated the impact wear damage to the materials,which should be avoided.

关键词： Dissimilar welded joint Impact wear Bainitic steel Damage mechanism Wear rate

Bioinspired design of integral molded Janus silk fibroin-MXene evaporator for efficient solar vapor generation

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Nano Research 2024年第4期17卷 2824-2835页

作者： Ling-Qing Kong zhi-Cheng zeng guang-Zong Min Zhao-Hui Meng Guo-Qing Meng Xiao-Xiao Guo Nai-Bo Lin Xiang-Yang Liu The Higher Educational Key Laboratory for Biomedical Engineering of Fujian Province Research Center of Biomedical Engineering of XiamenDepartment of BiomaterialsCollege of MaterialsXiamen UniversityXiamen 361005China The State Key Laboratory of Marine Environmental Science(MEL) College of Ocean and Earth SciencesXiamen UniversityXiamen 361005China

Solar vapor generation is a promising sustainable technology that uses solar distillation to produce fresh water from seawater and wastewater,helping relieve global water resource ***,inspired by naturally grown integrally molded mulberry leaves with a Janus hydrophilic and hydrophobic structure,a novel,simple,and efficient integrated molding method is proposed to break through the limitations of the traditional split manufacturing strategy and realizes the integrated formation of Janus *** on the spontaneous sedimentation characteristics of MXene in silk fibroin solution and its regulation of mesoscopic structure and hydrophilicity of silk fibroin,layered structures with different compositions and hydrophilicities were obtained in one ***,ethanol and glutaraldehyde were added to construct a physical crystallization-chemical crosslinking dual stabilization structure in silk *** evaporator has the evaporation rate of 3.07 kg·m^(-2)·h^(-1) and the efficiency of 86.8%under 1 sun and maintains high evaporation performance under various extreme test conditions including vigorous washing,repeated compression,and high-intensity ultraviolet(UV)***,the evaporator performs well in practical application scenarios,its evaporation rate in the simulated Dead Sea seawater exceeds 2.13 kg·m^(-2)·h^(-1),and more than 99.9%of the salt,heavy metal ions,oil pollution,and dyes are purified.

关键词： silk fibroin MXene bioinspired integrated molding Janus structure solar vapor generation

Switching,explosion,and chaos of multi-wavelength soliton states in ultrafast fiber lasers

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Science China(Physics,Mechanics & Astronomy) 2024年第7期67卷 82-90页

作者： zhi-zeng Si Yue-Yue Wang Chao-Qing Dai College of Optical Mechanical and Electrical EngineeringZhejiang A&F UniversityLin’an 311300China

Because of the complexity and difficulty of realizing a multi-wavelength soliton state,reports on its internal dynamic characteristics are *** this study,the switching and periodic soliton explosion processes of the multi-wavelength soliton state in a negative dispersion passively mode-locked fiber laser are *** generation of the multi-wavelength soliton state undergoes the process of noise,oscillation,and stable mode-locking,and the splitting and annihilation of solitons with different group velocities directly impact the generation and disappearance of three *** and negative dispersion lead to different group velocities of *** presence and displacement of solitons with different group velocities cause soliton collisions,which lead to soliton explosions.A soliton experiences relative phase oscillation,chaos,and oscillation,as well as convergence and separation before and after an *** an increase in parameters related to pump power,single-soliton oscillation,multi-wavelength solitons,and chaos are found in experiments and simulations,proving the relevance and reliability between simulation and experimental *** work promotes the dynamical study of multi-soliton collisions in nonlinear science and the development of chaos theory in multi-comb lasers.

关键词： multi-wavelength fiber laser soliton explosion chaos state switching real-time dynamics

Subclinical impairment of left ventricular myocardium function in type 2 diabetes mellitus patients with or without hypertension

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World Journal of Diabetes 2024年第6期15卷 1272-1279页

作者： zeng-guang Chen guang-An Li Jun Huang Li Fan Department of Cardiology The Affiliated Changzhou Second People’s Hospital with Nanjing Medical UniversityChangzhou 213000Jiangsu ProvinceChina Department of Echocardiography The Affiliated Changzhou Second People’s Hospital with Nanjing Medical UniversityChangzhou 213000Jiangsu ProvinceChina

BACKGROUND Cardiovascular disease has been the leading cause of morbidity and mortality for type 2 diabetes mellitus(T2DM)patients over the last *** To determine whether layer-specific global longitudinal strain(GLS)combined with peak strain dispersion(PSD)can be used to assess left ventricle(LV)myocardium systolic dysfunction in T2DM patients or without hypertension(HP).METHODS We enrolled 97 T2DM patients,70 T2DM+HP patients and 101 healthy ***-specific GLS and PSD were calculated by EchoPAC software in apical three-,four-and two-chamber *** of the epimyocardial,middle-layer and endomyocardial(GLSepi,GLSmid,and GLSendo)were measured and *** operating characteristic analysis was performed to detect LV myocardium systolic dysfunction in T2DM *** There were significant differences in GLSepi,GLSmid,GLSendo,and PSD between healthy subjects,T2DM patients and T2DM patients with HP(PT2DM patients>T2DM with HP patients in the absolute values of GLSepi,GLSmid and GLSendo(P<0.001),while PSD was ranked healthy subjects

关键词： Type 2 diabetes mellitus Hypertension Speckle tracking echocardiography Global longitudinal strain Peak strain dispersion