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Crystal Structure and Luminescent Properties of a New Rare-earth Borate K3Pr3（BO3）4

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Chinese Journal of Structural Chemistry 2019年第5期38卷 727-736,668页

作者： SHI Jian-Chao ZHAO Dan xue ya-li ZHANG Shi-Rui li Fei-Fei College of Chemistry and Chemical Engineering Henan Polytechnic University

A new borate K3Pr3（BO3）4 has been prepared using a high temperature flux method and structurally characterized by single-crystal X-ray diffraction *** crystallizes in triclinic system,space group ■ with a=9.0814（10）,b=10.8052（12）,c=14.0885（16）?,α=69.800（1）°,β=89.922（1）o,γ=89.892（1）°,V=1297.4（3）?3,Z=4,Mr=775.27,Dc=3.969 g/cm3,F（000）=1400,μ（MoKα）=12.11 mm-1,R（F2>2σ（F2））=0.028 and wR（F2）=***,the crystal of K3Pr3（BO3）4 was twinned by pseudo-merohedry that is mimic monoclinic space group P2/*** structure of K3Pr3（BO3）4 exhibits a three-dimensional（3D）network based on isolated anionic（BO3）3- units that are further bridged by K+and Pr3+***,X-ray diffraction（XRD）,IRspectrum and photoluminescence（PL）properties were studied.

关键词： borate X-ray diffraction twinning photoluminescence

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

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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

Citrinsorbicillin A,a novel homotrimeric sorbicillinoid isolated by LC-MS-guided with cytotoxic activity from the fungus Trichoderma citrinoviride HT-9

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Chinese Chemical Letters 2024年第8期35卷 299-303页

作者： Guo-Ping Yin ya-Juan li li Zhang ling-Gao Zeng xue-Mei liu Chang-Hua Hu Engineering Research Center of Coptis Development and Utilization(Ministry of Education) College of Pharmaceutical Sciences and Chinese MedicineSouthwest UniversityChongqing 400715China State Key Laboratory of Natural Medicines China Pharmaceutical UniversityNanjing 211198China NMPA Key Laboratory for Quality Monitoring of Narcotic Drugs and Psychotropic Substances Chongqing Institute for Food and Drug ControlChongqing 401121China

Citrinsorbicillin A(1),a novel homotrimeric sorbicillinoid,along with two new monomers citrinsor-bicillins B(2)and C(3),were isolated from the Coptis chinensis endophyte Trichoderma citrinoviride HT-9 by liquid chromatograph mass spectrometer(LC-MS)-guided strategy.1 was the first trimeric-example from terrestrial fungi,which possessed a unique carbon skeleton with two bicyclo[2.2.2]octanedione ring connected through an enolated carbon forming by[4+2]*** structures were elucidated by spectroscopic analysis and X-ray diffraction.1 exhibited moderate cytotoxicity against human colon cancer HT29 cells,and it induced significant cell cycle arrest by reducing the protein expression of cyclin D1.

关键词： Citrinsorbicillin A Trimeric sorbicillinoid Coptis chinensis endophyte Trichoderma citrinoviride [4+2]Cycloaddition Cytotoxic activity

Expression and Significance of NF-κB, IL-1β and COX-2 in the Murine Model of Estrogen-dependent Experimental Vulvovaginal Candidiasis

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Journal of Reproduction and Contraception 2007年第4期18卷 253-260页

作者： xue-rong CHEN ya-li liU Dun-zhen XIAO Jun GAO Reproductive Medicine Center Research Institute of Family Planning Tongji Medical College Huazhong University of Science and Technology Wuhan 430030 China

Objective To investigate the possible role of estrogen in the pathogenesis of vulvovaginal candidiasis（VVC）. Methods Estrogen-dependent experimental murine model of C. albicans vaginal infection was established by injecting subcutaneously with estradiol benzoate and then 5 × 10^6 stationary-phase C. albicans blastoconidia was inoculated intravaginally to mice （group El）, and other 3 groups were set up.＂ estrogen-treated but not infected （group E）; estrogen-untreated but infected （group I）; normal control （group C）. The dynamic change of colony-forming unit （CFU） of cervivovaginal lavage fluid was observed. Vaginal tissues at different time points （d 2, d 4, d 7 and d 14） after inoculation of C. albicans were obtained. In situ hybridization staining was used to detect expression of cyclooxygenase-2 （COX-2） mRNA and expression of nuclear factor-κB （NF-κB） was examined by immuohistochemistry. EliSA was applied to determine the interlenkin-1β （IL-1β） level. Results The constitutional high level expression of COX-2 mRNA in the vaginal tissue of group E was significantly higher than that in group C on d 4 and d 7 （P〈0. 01）, and the optical density （OD） in group EI was higher than that in the other 3 groups （P〈0.05）. There were higher IL-1β levels in vaginal tissues from d 4 to d 7 postinoculation in group EI and group I than group C （P〈0.01）. Furthermore, IL-1β in group EI was markedly elevated on d 4 and d 7 compared with group I （P〈0.01）. Compared with group C, the expression of NF-κB in group E was increased obviously on d 4 （P〈0.01）, and there was significant difference between group E1 and group I on d 4 and d 7 （P〈0.01）. Conclusions In the murine model of estrogen-dependent experimental WC, estrogen promotes the infection establishment by up-regulating expression of COX-2 via activating NF-κB signal pathway, and the high expression of COX-2 promoted by the interaction of IL-1β and NF-κB after infection formation was involved in persistence of infection.

关键词： estrogen Candida albicans vaginitis COX-2 IL-1β NF-κB

Research on shell-side heat and mass transfer with multi-component in LNG spiral-wound heat exchanger under sloshing conditions

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Petroleum Science 2024年第2期21卷 1333-1345页

作者： xue-Ping Du Guang-Lei Yu ya-Cheng Xu Zhi-Jie Chen Nai-liang li Huan-Guang Wang School of Low-carbon Energy and Power Engineering China University of Mining and TechnologyXuzhou221116JiangsuChina Key Laboratory of Thermo-Fluid Science and Engineering MOEXi'an Jiaotong UniversityXi'an710049ShaanxiChina Xi'an Aerospace Propulsion Test Technology Institute Xi'an710100ShaanxiChina

The spiral-wound heat exchanger(SWHE) is the primary low-temperature heat exchanger for large-scale LNG plants due to its high-pressure resistance, compact structure, and high heat exchange efficiency. This paper studied the shell-side heat and mass transfer characteristics of vapor-liquid two-phase mixed refrigerants in an SWHE by combining a multi-component model in FLUENT software with a customized multicomponent mass transfer model. Besides, the mathematical model under the sloshing condition was obtained through mathematical derivation, and the corresponding UDF code was loaded into FLUENT as the momentum source term. The results under the sloshing conditions were compared with the relevant parameters under the steady-state condition. The shell-side heat and mass transfer characteristics of the SWHE were investigated by adjusting the component ratio and other working conditions. It was found that the sloshing conditions enhance the heat transfer performance and sometimes have insignificant effects. The sloshing condition is beneficial to reduce the flow resistance. The comprehensive performance of multi-component refrigerants has been improved and the improvement is more significant under sloshing conditions, considering both the heat transfer and pressure *** results will provide theoretical support for the research and design of multi-component heat and mass transfer enhancement of LNG SWHE under ocean sloshing conditions.

关键词： Spiral-wound heat exchanger Sloshing conditions Two-phase flow Multi-component Heat and mass transfer

Investigation and measurement of old building response to the overlapped shield tunnel of multiple schemes in the sandy cobble stratum

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Underground Space 2024年第2期15卷 260-274页

作者： xue li Aopeng Geng School of Geoscience and Technology Southwest Petroleum UniversityChengduSichuan 610500China China Railway Construction Bridge Engineering Bureau Group Co. Ltd.Tianjin 300300China

Ground movements due to tunneling are becoming increasingly critical as buildings are located around construction *** study proposes a new combined reinforcement method using a foundation grouting oblique pipe *** former improves the bearing capacity of the subsoil,and the latter blocks the transmission of soil deformation,which weakens the influence of construction during overlapped tunnel *** on this new method,a case study of the shield tunneling response to an old building in line 6 of China’s Chengdu Metro is ***,three-dimensional numerical models without reinforcement,traditional foundation grouting reinforcement,and the new combined reinforcement schemes were *** numerical simulation performance was verified using a set of field instrumentation data,which demonstrated that the old building response to the overlapped tunnels was under control,and the maximum deformation,angular distortion,and principal tensile strain of the building were 5.25 mm,5.1010–6 rad/m,and 0.0081%,*** with the traditional reinforcement scheme,the deformation,angular distortion,and principal tensile strain in the combined reinforcement scheme were reduced by 54.78%,71.02%,and 70.22%,*** results have important implications for the design and construction of shield tunnels and their response to old buildings.

关键词： Overlapped tunnels Reinforcement schemes Under-crossing Old building Numerical simulation

Cracking on a nickel-based superalloy fabricated by direct energy deposition

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China Foundry 2024年第4期21卷 311-318页

作者： xue Zhang ya-hang Mu liang Ma Jing-jing liang Yi-zhou Zhou Xiao-feng Sun Jin-guo li School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China Shi-changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering Northeastern UniversityShenyang 110819China

Cracks have consistently been a significant challenge limiting the development of additive manufactured nickel-based *** is essential to investigate the location of cracks and their forming *** study extensively examines the impact of solidification process,microstructural evolution,and stress concentration on crack initiation during direct energy deposition(DED).The results emphasize that the crack formation is significantly related to large-angle grain boundaries,rapid cooling *** caused by large-angle grain boundaries and a fast-cooling rate predominantly appear near the edge of the deposited *** cracks are more likely to form near the top of the deposited sample,due to the presence ofγ/γ'*** secondary dendritic arm and the carbides in the interdendritic regions can obstruct liquid flow during the final stage of solidification,which results in the formation of solidification cracks and *** work paves the way to avoid cracks in nickel-based superalloys fabricated by DED,thereby enhancing the performance of superalloys.

关键词： location cracks direct energy deposition nickel-based superalloys

Age and mean platelet volume-based nomogram for predicting the therapeutic efficacy of metoprolol in Chinese pediatric patients with vasovagal syncope

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World Journal of Pediatrics 2024年第9期20卷 957-965页

作者： Xiao-Juan Du ya-Qian Huang xue-Ying li Ying liao Hong-Fang Jin Jun-Bao Du Department of Pediatrics Peking University First HospitalNo.1 Xi’anmen StreetWest DistrictBeijing100034China State Key Laboratory of Vascular Homeostasis and Remodeling Peking UniversityNo.38Xueyuan RoadHaidian DistrictBeijing100191China Department of Statistics Peking University First HospitalBeijing100034China

Background Vasovagal syncope(VVS)is the most common type of orthostatic intolerance in *** investigated whether platelet-related factors related to treatment efficacy in children suffering from VVS treated with *** Metoprolol-treated VVS patients were *** median duration of therapy was three *** were followed and divided into two groups,treament-effective group and treatment-ineffective *** and least absolute shrinkage selection operator regressions were used to examine treatment outcome ***-operating characteristic(ROC)curves,precision-recall(PR)curves,calibration plots,and decision curve analyses were used to evaluate the nomogram *** Among the 72 patients who complete the follow-up,treatment-effective group and treatment-ineffective group included 42(58.3%)and 30(41.7%)cases,*** patients in the treatment-effective group exhibited higher mean platelet volume(MPV)[(11.0±1.0)fl vs.(9.8±1.0)fl,Plinical *** A novel nomogram based on age and MPV can predict the therapeutic benefits of metoprolol in children with VVS.

关键词： Metoprolol Nomogram Retrospective study Therapeutic effect Vasovagal syncope

Ground state of Rydberg-dressed Bose gas confined in a toroidal trap

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Communications in Theoretical Physics 2024年第1期76卷 29-35页

作者： lin-xue Wang Hong-li yang Hui liu Si-lin Chen ya-Jun Wang Xiao-Fei Zhang Department of Physics School of Physics and Information ScienceShaanxi University of Science and TechnologyXi'an 710021China Department of Basic Sciences Air Force Engineering UniversityXi'an 710051China

The experimental realization of Rydberg dressing technology in ultracold atomic systems provides another superior platform for studying novel states of matter and macroscopic quantum *** this work,based on the mean-field theory,we have investigated the ground-state phases of a two-component Bose–Einstein condensate with Rydberg interaction and confined in a toroidal *** effects of the Rydberg interaction and external potential,especially the Rydberg blockade radius,on the ground-state structure of such a system have been investigated in full parameter *** results show that the Rydberg blockade radius,which can be regarded as another controllable parameter,can be used to obtain a variety of ground-state *** interestingly,it is found that for weak Rydberg interactions,the Rydberg blockade radius breaks the spontaneous rotational symmetry of the system,leading to the formation of a discrete unit cell *** strongly interacting cases,it can be used to realize different orders of discrete rotational symmetry breaking.

关键词： Bose-Einstein condensate Rydberg dressing toroidal trap