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Journal of Hydrodynamics 2024年第1期36卷 184-201页

作者： Xiao-qi jia Shuai-kang Zhang Zu-chao Zhu Key Laboratory of Fluid Transmission Technology of Zhejiang Province Zhejiang Sci-Tech UniversityHangzhou310018China

To reveal the cavitation forms of tip leakage vortex(TLV)of the axial flow pump and the flow mechanism of the flow field,this research adopts the partially-averaged Navier-Stokes(PANS)model to simulate the cavitation values of an axial flow pump,followed by experimental *** experimental result shows that compared with the shear stress transport(SST)k-ωmodel,the PANS model significantly reduces the eddy viscosity of the flow field to make the vortex structure clearer and allow the turbulence scale to be more robustly *** cavitation area within the axial flow pump mainly comprises of TLV cavitation,clearance cavitation and tip leakage flows combined effect of triangular cloud cavitation *** formation and development of cavitation are accompanied by the formation and evolution of vortex,and variations in vortex structure also generate and promote the development of *** addition,an in-depth analysis of the relationship between the turbulent kinetic energy(TKE)transport equation and cavitation patterns was also conducted,finding that the regions with relatively high TKE are mainly distributed around gas/liquid boundaries with serious cavitation and evident gas-liquid *** phenomenon is mainly attributed to the combined effect of the pressure action term,stress diffusion term and TKE production term.

关键词： Cavitation axial flow pump tip leakage vortex(TLV) partially-averaged Navier-Stokes(PANS)model turbulent kinetic energy(TKE)

Three Types of Expression in Dark-Soliton Perturbation Theory Based on Squared Jost Solutions

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Communications in Theoretical Physics 2007年第1期47卷 15-18页

作者： AO sheng-Mei YAN jia-Ren College of Physics and Information Science Hunan Normal University Changsha 410081 China

Three types of expression in the dark-soliton perturbation theory based on squared Jost solutions are invesgigaged in ghis paper. It is shown that there are three formally different results about the effects of perturbagion on a dark soliton, and it is proved by means of a transformation between two integral variables that they are essentially equivalent.

关键词： dark soliton perturbation theory squared Jost solution soliton velocity first-order correction

Blood Lead Levels During Pregnancy and Its Influencing Factors in Nanjing,China

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Chinese Medical Sciences Journal 2013年第2期28卷 95-101页

作者： kang-sheng Liu jia-hu Hao Juan Shi Chun-fang Dai Xi-rong Guo State Key Laboratory of Reproductive Medicine Department of Clinical LaboratoryNanjing Maternity and Child Health Care Hospital Affiliated to Nanjing Medical University Department of Maternity Child Health Care School of Public HealthAnhui Medical University Child Health Care Department Nanjing Maternity and Child Health Care Hospital Department of Obstetrics Nanjing Maternity and Child Health Care Hospital Director's Office Nanjing Maternity and Child Health Care Hospital

Objective To investigate the blood lead levels （BLLs） in the duration of pregnancy and 6-12 weeks after delivery, and analyze the influencing factors of BLLs in healthy pregnant women. Methods Pregnant women were recruited from September 2009 to February 2010 at the prenatal clinic in Nanjing Maternity and Child Health Care Hospital. Altogether 174 healthy pregnant women without pregnant or obstetric complications or abnormal pregnancy outcomes were enrolled as the gravida group, and 120 healthy non-pregnant women as the control group. BLLs during pregnancy were determined by flame atomic absorption spectroscopy. Results BLLs in all the three pregnancy trimesters and postpartum were 59.8±24.3, 55.4±20.1, 55.9±19.7, and 67.6±17.4 μ/L, respectively, and the mean BLL in control group was 67.5±21.3 μg/L. BLLs during all the three trimesters were lower in the gravida group than in the control group （P=0.043, 0.021, and 0.028）. Furthermore, occupations, nutrients supplementation, and time of house/apartment painted were associated with BLLs in pregnant women. Lead-related occupations, cosmetics use, and living in a house painted less than 1 year before are risk factors of high BLLs among pregnant women, while calcium, iron, zinc, and milk supplements are protective factors. Conclusion Supplementing calcium, iron, zinc, and milk, or avoiding contact with risk factors may help people, especially pregnant women, to reduce lead exposure.

关键词： blood lead levels pregnancy lead exposure

Neurotoxicity and Biomarkers of Lead Exposure: a Review

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Chinese Medical Sciences Journal 2013年第3期28卷 178-188页

作者： kang-sheng Liu jia-hu Hao Yu Zeng Fan-chun Dai Ping-qing Gu State Key Laboratory of Reproductive Medicine Department of Clinical Laboratory Nanjing Maternity and Child Health Care Hospital Affiliated to Nanjing Medical University Department of Maternity and Child Health Care School of Public HealthAnhui Medical University Child Health Care Department Nanjing Maternity and Child Health Care Hospital Affiliated to Nanjing Medical University Obstetrical Department Nanjing Maternity and Child Health Care Hospital Affiliated to Nanjing Medical University Department of Epidemiological and Health Statistics School of Public Health of Nanjing Medical University

Appropriate selection and measurement of lead biomarkers of exposure are critically important for health care management purposes,public health decision making,and primary prevention *** is one of the neurotoxicants that seems to be involved in the etiology of *** are generally classified into three groups:biomarkers of exposure,effect,and *** main body compartments that store lead are the blood,soft tissues,and bone;the half-life of lead in these tissues is measured in weeks for blood,months for soft tissues,and years for *** the brain,lead-induced damage in the prefrontal cerebral cortex,hippocampus,and cerebellum can lead to a variety of neurological disorders,such as brain damage,mental retardation,behavioral problems,nerve damage,and possibly Alzheimer’s disease,Parkinson’s disease,and *** paper presents an overview of biomarkers of lead exposure and discusses the neurotoxic effects of lead with regard to children and adults.

关键词： lead poisoning biological monitoring neurotoxicity neurodevelopment

Relationship between red blood cell distribution width and intermediate-term mortality in elderly patients after percutaneous coronary intervention

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Journal of Geriatric Cardiology 2015年第1期12卷 17-22页

作者： Xin-Min LIU Chang-sheng MA Xiao-Hui LIU Xin DU Jun-Ping kang Yin ZHANG jia-Hui WU Department of Cardiology Beijing An Zhen Hospital Capital Medical University Beijing 100029 China

Background Large-scale clinical research on the relationship between red blood cell distribution width （RDW） and intermediate-term prognosis in elderly patients with coronary artery disease （CAD） is lacking. Thus, this study investigated the effects of RDW on the intermediate-term mortality of elderly patients who underwent elective percutaneous coronary intervention （PCI）. Methods Data from 1891 patients 〉 65 years old underwent elective PCI from July 2009 to September 2011 were collected. Based on preoperative median RDW （12.3%）, the patients were divided into two groups. The low RDW group （RDW 〈 12.3%） had 899 cases; the high RDW group （RDW 〉 12.3%） had 992 cases. The all-cause mortality rates of the two groups were compared. Results Patients in the high RDW group were more likely to be female and accompanied with diabetes, had lower hemoglobin level. The mean follow-up period was 527 days. During follow-up, 61 patients died （3.2%）. The postoperative mortality of the high RDW group was significantly higher than that of the low RDW group （4.3% vs. 2.0%, P = 0.004）. After adjusting other factors, multivariate Cox regression analysis revealed that preoperative high RDW was significantly associated with postoperative all-cause mortality （hazard ratio： 2.301, 95% confidence interval： 1.106-4.785, P = 0.026）. Conclusions Increased RDW was an independent predictor of the increased intermediate-term all-cause mortality in elderly CAD patients after elective PCI.

关键词： Coronary artery disease Elderly patients Percutaneous coronary intervention Red blood cell distribution width

Theoretical connotation and main focus of“supply-side reform”

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China Finance and Economic Review 2016年第1期5卷 3-13页

作者： jia kang Ministry of Finance China China Academy of New Supply-side Economics

Based on the comprehensive reform after the 18th National Congress of the Communist Party of China(CPC),the Fifth Plenary Session of the 18th CPC Central Committee proposed a systematized and modern strategy for *** proposal regards innovative development as a primary driving force,and incorporates coordinated development,green development,and open development-ultimately converging on shared ***,policymakers articulated the guiding opinion of“putting forth efforts in promoting supply-side structural reform”,which elicited extensive attention and *** paper mainly focuses on the theoretical connotation and suggestions of supply-side reform.

关键词： supply-side reform institutional supply

Two-order Hermite vector-interpolating subdivision schemes

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第9期7卷 1566-1571页

作者： FAN Min kang Bao-sheng ZHAO Hua Beijing Institute of Tracking and Telecommunication Technology Beijing 100094 China Department of Computer Sctence Northwest University Xi＇an 710069 China

A family of two-order Hermite vector-interpolating subdivision schemes is proposed and its convergence and con- tinuity are analyzed. The iterative level can be estimated for given error. The sufficient conditions of C2 continuity are proved. Geometric features of subdivision curves, such as line segments, cusps and inflection points, are obtained by appending some conditions to initial vectorial Hermite sequence. An algorithm is presented for generating geometric features. For an initial se- quence of two-order Hermite elements from unit circle, the numerical error of the 4th subdivided level is O(10?4).

关键词： Two-order vectorial Hermite element Hermite-interpolating subdivision schemes Geometric features

Mainchain Semifluorinated Polymers with Ultra High Molecular Weight via Reaction-enhanced Reactivity of Intermediate(RERI) Mechanism

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Chinese Journal of Polymer Science 2023年第5期41卷 760-767,I0009页

作者： jia-sheng Wu Wang-Meng Hou Zhi-jia Liu Yi Shi Yong-Ming Chen School of Materials Science and Engineering Key Laboratory for Polymeric Composite and Functional Materials of Ministry of EducationSun Yat-Sen UniversityGuangzhou 510006China

Achieving the linear polymers with high molecular weight via step-growth polymerization of A2 and B2 monomers is significantly limited by the requirement of strict stoichiometry of two monomers when the reactivity of A and B groups are not changed during the ***,a unique step-growth polymerization based on copper-catalyzed azide-alkyne cycloaddition(CuAAC)with reactionenhanced reactivity of intermediate(RERI)mechanism was developed for the preparation of mainchain semifluorinated polymers with high molecular *** CuAAC polymerization of bis-alkynyl-terminated fluorinated monomers(A2)and 2,2-bis(azidomethyl)propane-1,3-diyl bis(2-methylpropanoate)(BiAz,B2)with RERI effect at different stoichiometric ratio was systematically *** results indicated that the semifluorinated polymers with ultrahigh molecular weight,Mw,MALLS>106 g/mol,could be efficiently synthesized by using excess molar of BiAz *** resultant high-molecular-weight semifluorinated polymers show good thermostability and high *** addition,the glass transition temperature(Tg)of these mainchain semifluorinated polymers could be tuned conveniently due to the bis-alkynyl-terminated comonomers could be consumed completely when excessive BiAz monomers were used in this this step-growth polymerization.

关键词： Semifluorinated polymers Click polymerization Step-growth polymerization

On abundant wave structures of the unsteady korteweg-de vries equation arising in shallow water

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Journal of Ocean Engineering and Science 2023年第6期8卷 595-601页

作者： kang-jia Wang Jing-Hua Liu School of Physics and Electronic Information Engineering Henan Polytechnic UniversityJiaozuo 454003China

The aim of this paper is to study the unsteady korteweg-de vries equation that plays an important role in describing the shallow *** analytical techniques namely the Sardar-subequation method and the energy balance method are employed to seek the abundant traveling wave solutions for the first *** these two methods,plenty of traveling wave solutions such as the bright solitary wave solutions,dark solitary wave solutions,singular periodic wave solutions and perfect periodic wave solution that expressed in terms of the generalized hyperbolic functions,generalized trigonometric functions and the cosine function are ***,the dynamic behaviors of the solutions are described through the 3D plot and 2D *** results in this paper demonstrate that the proposed methods are powerful and effective to construct the traveling wave solutions of the nonlinear evolution equations in ocean engineering and science.

关键词： Sardar-subequation method Energy balance method Unsteady korteweg-de vries equation Solitary wave solution Periodic wave solution

Science Letters:Determination of benzalkonium chloride in viscous ophthalmic drops of azithromycin by high-performance liquid chromatography

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2009年第12期10卷 877-882页

作者： Yan SHEN sheng-jie XU Shi-chun WANG jia-sheng TU Department of Pharmaceutics China Pharmaceutical University Nanjing 210009 China Productivity Center of jiangsu Province Nanjing 210042 China

A high-performance liquid chromatography （HPLC） system was used in the reversed phase mode for the determination ofbenzalkonium chloride （BKC） in azithromycin viscous ophthalmic drops. A Venusil-XBP（L）-C18 （150 mm×4.6 mm, 5 gm） column was used at 50℃. The mobile phase consisted of a mixture of methanol-potassium phosphate （16：5, v/v）. Two sample preparation methods were compared. The results suggested that, compared with an extraction procedure, a deproteinization procedure was much quicker and more convenient. Using the deproteinization procedure for sample preparation, calibration curves were linear in the range 5.0-50μg/ml. The within-day and inter-day coefficients of variation were less than 10%. The average recoveries were determined as 96.70%, 98.52%, and 97.96% at concentrations of 10.0, 30.0, and 50.0 μg/ml, respectively. Variability in precision did not exceed 5%. In conclusion, this HPLC method using a simple sample treatment procedure appears suitable for monitoring BKC content in azithromycin viscous ophthalmic drops.

关键词： Benzalkonium chloride High-performance liquid chromatography Azithromycin Viscous ophthalmic drops