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Flowfield of a helicopter submerged inlet with power output shaft

Acta Mechanica Sinica 2021年第1期37卷 156-168,I0003页

作者： He-Xia Huang Hui-Jun Tan Zheng-kang lin Zi-Jie Li Shu Sun Hao Chen Zhi-Xiang Xiao Jiangsu Province Key Laboratory of Aerospace Power System College of Energy and Power EngineeringNanjing University of Aeronautics and AstronauticsNanjing210016China School of Aerospace Engineering Tsinghua UniversityBeijing100084China

The submerged inlet is an attractive configuration for advanced helicopters due to its high stealth performance and low external *** this paper,a submerged inlet,integrated with a ROBIN helicopter fuselage and a simplified power output shaft,is experimentally and numerically investigated to obtain the basic flow characteristics under a freestream velocity of 23.6 m/*** results indicate that the pylon ahead of the inlet induces a horseshoe *** the vortex is ingested into the inlet,it has little effect on the internal flows and can be *** the airflow enters into the inlet,it interacts with the shaft with a large incidence angle,yielding a vortex *** the leeside of the shaft,the two side flows of the shaft impinge at the center plane,generating a local high-pressure region at the azimuthal angle of 180°,which forces the boundary layer to roll up a counter-rotating vortex *** addition,the airflow adjacent to the cowl lip accelerates rapidly,resulting in a local low-pressure region at the azimuthal angle of 0°.Therefore,the inlet duct has a strong circumferential pressure gradient,which originates from an azimuthal angle of 180°to 0°and induces a vortex pair at the azimuthal angle of 0°.The three vortex pairs are the main origins of the distortion at the duct exit plane,among which the one near the cowl lip with the azimuthal angle of 0°plays the dominant ***,as the velocity ratio increases from 3.9 to 5.5,the circumferential pressure gradient and the cowl lip vortex get intensified,which causes that the total-pressure recovery coefficient drops by 0.5%and the distortion index increases by 28%.

关键词： Submerged inlet Helicopter Vortex pair

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Effect of Ti on microstructure and strengthening behavior in press hardening steels

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Journal of Central South University 2017年第10期24卷 2215-2221页

作者： WEN Yu-hui ZHU Guo-ming DAI Si-yu kang Yong-lin School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China State Key Laboratory for Advanced Metals and Materials(University of Science and Technology Beijing) Beijing 100083China

Effect of Ti addition on the microstructure and strengthening behavior in press hardening steels(PHS)was analyzed by optical metallography(OM),scanning electron microscopy(SEM),transmission electron microscopy(TEM)and X-ray diffraction(XRD).The results show that the microstructure of PHS is martensite,and two sizes of particles disperse in the martensite matrix during the forming and quenching *** size of the bigger particles is between 100 and 200 nm,and the small particles are *** quantity of the particles has a positive relation with the Ti *** importantly,the microstructure and strengthening mechanism are affected by the precipitating behavior of the *** the prior austenite grain,martensite packet,block and lath are refined by Ti *** steels are strengthened by the fine grains,martensite substructure and *** uniformly distributed dislocation in the martensite lath,the density of which is between 3.0?10^(14) cm^(–2) and 5.0?10^(14) cm^(–2),strengthens the steels through associating with fine carbide particles.

关键词： martensite particles prior austenite grain martensite lath press hardening steel

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Preliminary neutron study of a thorium-based molten salt energy amplifier

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Nuclear Science and Techniques 2020年第4期31卷 106-117页

作者： Pu Yang Zuo-kang lin Wei-shi Wan Gui-Feng Zhu Xiao-Han Yu Zhi-Min Dai Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China ShanghaiTech University Shanghai 201210China

Present designs for molten salt thermal reactors require complex online processing systems, which are technologically challenging, while an accelerator-driven subcritical molten salt system can operate without an online processing system, simplifying the design. Previous designs of accelerator-driven subcritical systems usually required very high-power proton accelerators(>10MW).In this research, a proton accelerator is used to drive a thorium-based molten salt fast energy amplifier(TMSFEA)that improves the neutron efficiency of the system. The research results show that TMSFEA can achieve a longterm stable state for more than 30 years with a rated power of 300 MW and a stabilizing effective multiplication factor(k(eff)) without any online processing. In this study, a physical design of an integrated molten salt energy amplifier with an initial energy gain of 117 was accomplished. According to the burn-up calculation, a molten salt energy amplifier with the rated power of 300 MW(th) should be able to operate continuously for nearly 40 years using a 1 Ge V proton beam below 4 m A during the lifetime. By the end of the life cycle, the energy gain can still reach 76,and^(233) U contributes 70.9% of the total fission rate, which indicates the efficient utilization of the thorium fuel.

关键词： Molten salt Energy amplifier Energy gain Conversion ratio Beam intensity

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Multifunctional oral delivery systems for enhanced bioavailability of therapeutic peptides/proteins

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Acta Pharmaceutica Sinica B 2019年第5期9卷 902-922页

作者： Ying Han Zhonggao Gao Liqing Chen lin kang Wei Huang Mingji Jin Qiming Wang You Han Bae State Key Laboratory of Bioactive Substance and Function of Natural Medicines Department of PharmaceuticsInstitute of Materia MedicaChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing100050China Department of Pharmaceutics and Pharmaceutical Chemistry the University of UtahSalt Lake CityUT84108USA

In last few years, therapeutic peptides/proteins are rapidly growing in drug market considering their higher efficiency and lower toxicity than chemical drugs. However, the administration of therapeutic peptides/proteins is mainly limited in parenteral approach. Oral therapy which was hampered by harsh gastrointestinal environment and poorly penetrating epithelial barriers often results in low bioavailability(less than 1%–2%). Therefore, delivery systems that are rationally designed to overcome these challenges in gastrointestinal tract and ameliorate the oral bioavailability of therapeutic peptides/proteins are seriously promising. In this review, we summarized various multifunctional delivery systems, including lipid-based particles, polysaccharide-based particles, inorganic particles, and synthetic multifunctional particles that achieved effective oral delivery of therapeutic peptides/proteins.

关键词： Multifunctional delivery systems Oral Bioavailability Macromolecules Peptides and proteins Gastrointestinal environment Epithelial barriers Nanoparticles

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Promotion by 5-Aminolevulinic Acid of Germination of Pakchoi （Brassica campestris ssp. chinensis var. communis Tsen et Lee） Seeds Under Salt Stress

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Journal of Integrative Plant Biology 2005年第9期47卷 1084-1091页

作者： Liang-Ju WANG Wei-Bing JIANG Hui LIU Wei-Qin LIU Lang kang Xi-lin HOU College of Horticulture Nanjing Agricultural University Nanjing 210095 China

The seed germination and seedling growth of pakchoi （Brassica campestris ssp. chinensis var. communis Tsen et Lee cv. Hanxiao） were not significantly inhibited until the concentration of NaCl was increased to 150 mmol/L. Treatment of pakchoi seeds with exogenous 5-aminolevulinic acid （ALA）, at concentrations ranging from 0.01 to 10.00 mg/L, promoted seed germination when seeds were stressed by salinity, whereas levulinic acid （LA）, an inhibitor of ALA dehydrase, significantly inhibited seed germination and seedling growth, suggesting that metabolism of ALA into porphyrin compounds was necessary for seed germination and seedling growth. Determination of respiratory rate during seed germination showed that ALA increased seed respiration under both normal conditions and salt stress. Furthermore, salt stress decreased levels of endogenous ALA, as well as heme, in etiolated seedlings. More salt-tolerant cultivars of pakchoi contained higher relative levels of endogenous ALA and heme under conditions of salt stress. These results indicate that salt stress may inhibit the biosynthesis of endogenous ALA and then heme, which is necessary for seed germination, and treatment of seeds with exogenous ALA prior to germination may be associated with the biosynthesis of heme.

关键词： 5-aminolevulinic acid (ALA) germination heme pakchoi respiration salt stress.

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A simple Fourier transform spectrometer for terahertz applications

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Chinese Science Bulletin 2012年第6期57卷 573-578页

作者： JIANG Yi LIANG Ming JIN BiaoBing kang lin XU WeiWei CHEN Jian WU PeiHeng Research Institute of Superconducting Electronics Nanjing UniversityNanjing 210093China

A simple Fourier transform spectrometer was designed and constructed for the measurement of detectors,sources,passive devices and materials in the terahertz(THz) *** can be operated at frequencies between 0.3 and 1.5 THz,using a 50-μm-thick Mylar-film beam *** spectral range can be changed by altering the thickness of the beam *** highest frequency resolution is 750 *** studied the properties of heterodyne detectors including superconductor mixers and semiconductor harmonic mixers,direct detectors including an InSb semiconductor bolometer,superconducting tunnel junctions and the Golay cell,and sources including Gunn oscillators and a microwave source with its multipliers,as well as various materials and passive devices including Si wafers and metal mesh filters.

关键词：傅里叶变换光谱仪太赫兹应用无源器件出现频率谐波混频器超导混频器超导隧道结

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Albumin–bilirubin grade as a predictor of survival in hepatocellular carcinoma patients with thrombocytopenia

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World Journal of Gastrointestinal Oncology 2024年第5期16卷 1763-1772页

作者： Zhong-Ran Man Xuan-Kun Gong kang-lin Qu Qing Pang Bin-Quan Wu Department of Hepatobiliary Surgery The First Affiliated Hospital of Bengbu Medical CollegeBengbu 233000Anhui ProvinceChina Department of Hepatobiliary Surgery Anhui No.2 Provincial People’s HospitalHefei 230041Anhui ProvinceChina

BACKGROUND The models for assessing liver function,mainly the Child–Pugh(CP),albuminbilirubin(ALBI),and platelet–ALBI(PALBI)classifications,have been validated for use in estimating the prognosis of hepatocellular carcinoma(HCC)***,thrombocytopenia is a common finding and may influence the prognostic value of the three models in *** To investigate and compare the prognostic performance of the above three models in thrombocytopenic HCC *** A total of 135 patients with thrombocytopenic HCC who underwent radical surgery were retrospectively *** scores on the CP,ALBI and PALBI classifications were estimated ***–Meier curves with logrank tests and Cox regression models were used to explore the significant factors associated with overall survival(OS)and recurrence-free survival(RFS).RESULTS The preoperative platelet counts were significantly different among the CP,ALBI and PALBI *** a median follow-up of 28 mo,39.3%(53/135)of the patients experienced postoperative recurrence,and 36.3%(49/135)*** analysis suggested thatα-fetoprotein levels,tumor size,vascular invasion,and ALBI grade were significant predictors of OS and *** to the multivariate Cox regression model,ALBI was identified as an independent prognostic ***,CP and PALBI grades were not statistically significant prognostic *** The ALBI grade,rather than CP or PALBI grade,is a significant prognostic indicator for thrombocytopenic HCC patients.

关键词： Hepatocellular carcinoma Thrombocytopenia Child-Pugh Albumin-bilirubin Platelet-albumin-bilirubin

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Prevalence and prognostic implications of sarcopenia in older patients with coronary heart disease

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Journal of Geriatric Cardiology 2019年第10期16卷 756-763页

作者： Ning ZHANG Wen-ling ZHU Xiao-Hong LIU Wei CHEN Ming-Lei ZHU lin kang Ran TIAN Department of Geriatrics Peking Union Medical College HospitalBeijingChina Department of Cardiology Peking Union Medical College HospitalBeijingChina Department of Clinical Nutrition Peking Union Medical College HospitalBeijingChina

Background Sarcopenia is a progressive and generalized skeletal muscle disorder that is associated with an increased likelihood of adverse outcomes, including falls, fractures, physical disability, and mortality. However, there have been few systematic studies of the prevalence and prognostic values of sarcopenia in older patients with coronary heart disease(CHD). This study aimed to investigate the prevalence of sarcopenia in hospitalized older patients with CHD, and to prospectively evaluate the effect of sarcopenia on the short-term prognosis of these patients. Methods Patients aged ≥ 65 years, with the diagnosis of CHD from Peking Union Medical College Hospital between December 2017 and November 2018, were included. Sarcopenia was diagnosed according to consensus of the Asian Working Group for Sarcopenia in 2014. Follow-up items included unscheduled return visits, occurrence of major adverse cardiac and cerebral events (MACCE), and all-cause mortality. The MACCE-free survival curve of sarcopenic and non-sarcopenic older patients with CHD was estimated by the Kaplan-Meier method. Cox regression analysis was used to analyze the association between sarcopenia and an unscheduled return visits, MACCE, and all-cause mortality. Results A total of 345 older patients with CHD were enrolled in the study, with a median age of 74 years. Among the patients, 78 (22.6%) were diagnosed with sarcopenia. During the follow-up time, there were significantly more unscheduled return visits in sarcopenic patients than in non-sarcopenic patients (34.2% vs. 21.8%,χ^2 = 4.418, P = 0.036), while there was no significant difference in the occurrence of MACCE (χ^2 = 2.869, P = 0.09) or all-cause mortality (χ^2 = 1.673, P = 0.196) between these patient groups. The Kaplan-Meier curve showed that the MACCE-free survival time of sarcopenic patients was significantly shorter than that in non-sarcopenic patients (χ^2 = 4.102, P = 0.043). After adjusting for sex, age, and the Charlson comorbidity

关键词： Coronary heart disease Older adult Prognosis Sarcopenia

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Novel multiplex stool-based assay for the detection of early-stage colon cancer in a Chinese population

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World Journal of Gastroenterology 2022年第24期28卷 2705-2720页

作者： Hui-Hong Jiang Si-Wei Xing Xuan Tang Ying Chen kang lin Lu-Wei He Mou-Bin lin Er-Jiang Tang Department of General Surgery Yangpu HospitalTongji UniversityShanghai 200090China Institute of Gastrointestinal Surgery and Translational Medicine Tongji University School of MedicineShanghai 200090China Department of Urology Ruijin HospitalShanghai Jiaotong University School of MedicineShanghai 200025China Center for Clinical Research and Translational Medicine Yangpu HospitalTongji UniversityShanghai 200090China

BACKGROUND Stool DNA(sDNA)methylation analysis is a promising,noninvasive approach for colorectal cancer screening;however,reliable biomarkers for detecting early-stage colon cancer(ECC)are lacking,particularly in the Chinese *** To identify a novel stool-based assay that can improve the effectiveness of ECC *** A blinded case-control study was performed using archived stool samples from 125 ECC patients,and 125 control subjects with normal *** cohort was randomly divided into training and test sets at a 1.5:1 *** bisulfite sequencing(TBSeq)was conducted on five pairs of preoperative and postoperative sDNA samples from ECC patients to identify DNA methylation biomarkers,which were validated using *** logistic regression analysis,a multiplex stool-based assay was developed in the training set,and the detection performance was further assessed in the test set and combined ***χ^(2)test was used to investigate the association of detection sensitivity with clinico-pathological *** Following TBSeq,three hypermethylated cytosine-guanine sites were selected as biomarkers,including paired box 8,Ras-association domain family 1 and secreted frizzled-related protein 2,which differed between the groups and were involved in important cancer *** sDNA panel containing the three biomarkers was constructed with a logistic *** operating characteristic(ROC)analysis revealed that this panel was superior to the fecal immunochemical test(FIT)or serum carcinoembryonic antigen for the detection of *** further found that the combination of the sDNA panel with FIT could improve the screening *** the combined set,the sensitivity,specificity and area under the ROC curve for this multiplex assay were 80.0%,93.6%and 0.918,respectively,and the performance remained excellent in the subgroup analysis by tumor *** addition,the detection sensitivity did not differ with tumor site,tumo

关键词： Colon cancer Early screening Stool biomarker DNA methylation Fecal immunochemical test

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Dual-lens beam compression for optical coupling in superconducting nanowire single-photon detectors

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Science Bulletin 2015年第16期60卷 1434-1438页

作者： Labao Zhang Chao Wan Min Gu Ruiying Xu Sen Zhang lin kang Jian Chen Peiheng Wu School of Electronic Science and Engineering Nanjing University

The optical coupling of superconducting nanowire single-photon detectors （SNSPDs） has always been restricted to a single-mode fiber for a limited detection area. In this study, for enhancing photon coupling, a dual-lens system operating at 2.2 K was used to compress the beam size on the basis of the Gaussian beam theory and geometric approximation. A magnification of approximately 0.3 was obtained, and a focused spot with diameter of approximately 10 ~m was measured from a multimode fiber. Assisted with the compressed beam, a system efficiency of 55 % （1550 nm） was achieved for a SNSPD with a detection area of 10 μm × 10 μm and 62.5 pm multimode fiber coupling. At the same time, a high speed of 106 MHz was measured with the proposed system. The realization of a highly compressed optical beam reduced the optical coupling requirement and helped maintain a high speed for the SNSPD.

关键词： Superconducting nanowire Single-photon Infrared detector Large detection area

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