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Impact of hillslope vegetation restoration on gully erosion induced sediment yield

Science China Earth Sciences 2006年第2期49卷 176-192页

作者： CHEN hao cai Qiangguo Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China

Facing the eco-environmental construction on the Loess Plateau, especially the vegeta-tion restoration in the semiarid areas, as well as the dam system engineering construction that is about to start, how can the vegetation restoration gain the optimum ecological benefits following the improvement of the preservation rates of trees and grass on the basis of guaranteeing water storage and silt trapping effects? What techniques should be taken to restore vegetation? These questions critical to environmental management on the Loess Plateau have to be settled urgently. According to the different macroscopic spatial distribution patterns of forest and grass on the Loess Plateau, this paper analyzes the macroscopic hillslope and gully management relationship in the middle Yellow River and weight of natural and human factors in erosion-induced sediment yield in the context of environmental background of the major silt producing areas. In light of the current status of the inte-grated management of small watersheds and soil and water conservation measure arrangement schemes of hillslopes and gullies on the Loess Plateau, this paper discusses the impact of vegetation restoration on gully erosion induced sediment yield and the effect of vegetation caused sediment re-duction. Studies indicate that there exists an erosional environmental background related to the natural and human activities in the sediment yield peak values of the sandy and coarse sandy areas in the middle Yellow River, sediment yield modulus is closely related to the synthetic effect of environ-mental elements, and the rainstorms, reclamation rate and forest coverage are the main factors af-fecting sediment yield modulus in the sandy and coarse sandy areas. The key to control soil erosion in the sandy and coarse sandy areas is the conversion of farmland into forestland and grassland, the reduction of reclamation rate and the increase of tree and grass vegetation. Small catchment man-agement should adhere to t

关键词： relationship between hillslope and gully erosion control, vegetation restoration, natural and human environmental element, Loess Plateau.

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A Jacobi-collocation method for solving second kind Fredholm integral equations with weakly singular kernels

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Science China Mathematics 2014年第10期57卷 2163-2178页

作者： cai hao Tao School of Mathematics and Quantitative Economics Shandong University of Finance and Economics

In this work,we propose a Jacobi-collocation method to solve the second kind linear Fredholm integral equations with weakly singular ***,we consider the case when the underlying solutions are sufficiently *** this case,the proposed method leads to a fully discrete linear *** show that the fully discrete integral operator is stable in both infinite and weighted square ***,we establish that the approximate solution arrives at an optimal convergence order under the two ***,we give some numerical examples,which confirm the theoretical prediction of the exponential rate of convergence.

关键词： second kind Fredholm integral equations with weakly singular kernels Jacobi-collocation methods stability analysis convergence analysis

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Hydrothermal synthesis and optical properties of Zn_(1-x)Mn_xS nanorods

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Particuology 2011年第5期9卷 533-536页

作者： Yangfeng Huang Yebin cai hao Liu School of Mechanical ＆ Electrical Engineering Guangdong University of Petrochemical Technology Maoming 525000 China

Zn1-xMnxS （x = 0-0.05） nanorods were successfully synthesized through a hydrothermal route. The morphology, composition and microstructure of Zn1-xMnxS nanorods were characterized respectively by X-ray diffraction （XRD）, scanning electron microscopy （SEM） and Raman spectrometer. The optical properties of Zn1-xMnxS nanorods were determineded by UV-Vis absorption spectroscopy and photo- luminescence （PL） emission spectroscopy. The results show that the introduction of Mn^2＋ on interstitial sites in ZnS lattice has significant influence on the Raman spectra, UV-Vis absorption spectra and PL emis- sion spectra. With the increase of Mn^2＋, the lengths of the sampled nanorods become shorter and the morphologies of the products show disorder accompanied by some nanoparticles. The absorption band edge shifts to longer wavelength. The intensity of the ZnS-related emission gradually becomes weaker, whereas, the Mn^2＋-related broad emission spectra located at 580 nm gradually red-shifts and increases. Occupation of Zn^2＋ sites in the lattice by Mn^2＋ ions results in lattice distortion and influences the energy level structure of ZnS. The Mn doping is found responsible for the changes in the defect-related emission of the ZnS nanorods.

关键词： Inorganic compound Chemical synthesis Nanostructures Optical properties

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Qualitative Analysis of A Sulfur-fumigated Chinese Herbal Medicine by Comprehensive Two-Dimensional Gas Chromatography and High-Resolution Time of Flight MassSpectrometry Using Colorized Fuzzy Difference Data Processing

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Chinese Journal of Integrative Medicine 2017年第4期23卷 261-269页

作者： cai hao CAO Gang ZHANG Hong-yan School of Pharmacy Nanjing University of Chinese MedicineNanjing 210023 China Research Center of Traditional Chinese Medicine Processing Technology Zhejiang Chinese Medical University Hangzhou 310053 China Zhejiang Cancer Hospital Hangzhou 310022 China

To investigate the chemical transformation of volatile compounds in sulfur-fumigated Radix Angelicae Sinensis. A comprehensive two-dimensional gas chromatography (GCxGC) and high-resolution time-of-flight mass spectrometry (HR-TOF/MS) with colorized fuzzy difference (CFD) method was used to investigate the effect of sulfur-fumigation on the volatile components from Radix Angelicae Sinensis. Twenty-five compounds that were found in sun-dried samples disappeared in sulfur-fumigated samples. Seventeen volatile components including two sulfur-containing compounds were newly generated for the first time in volatile oils of sulfur-fumigated Radix Angelicae Sinensis. The strategy can be successfully applied to rapidly and holistically discriminate sun-dried and sulfur-fumigated Radix Angelicae Sinensis. GCxGC-HR-TOF/MS based CFD is a powerful and feasible approach for the global quality evaluation of Radix Angelicae Sinensis as well as other herbal medicines.

关键词： Radix Angelicae Sinensis comprehensive two-dimensional gas chromatography and high-resolution time-of-flight mass spectrometry colorized fuzzy difference volatile components

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Safety of lamivudine treatment for chronic hepatitis B in early pregnancy

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World Journal of Gastroenterology 2012年第45期18卷 6645-6650页

作者： Wei Yi Min Liu hao-Dong cai Department of Obstetrics and Gynecology Beijing Ditan Hospital Affiliated to Capital Medical University Department of Hepatology Beijing Ditan Hospital Affiliated to Capital Medical University

AIM:To evaluate the safety of lamivudine(LAM) treatment for chronic hepatitis B in early ***:A total of 92 pregnant women who received LAM treatment either before pregnancy or in early pregnancy were enrolled in this *** of the pregnant women volunteered to take lamivudine during pregnancy and were not co-infected with hepatitis C virus,human immunodeficiency virus,cytomegalovirus,or other *** infants received passiveactive immunoprophylaxis with 200 IU hepatitis B immunoglobulin and three doses of 10 μg hepatitis B vaccines(0-1-6 mo) according to the guidelines for the prevention and treatment of chronic hepatitis *** events were observed throughout the entire pregnancy and perinatal period,and the effectiveness of lamivudine treatment for blocking mother-to-infant transmission of hepatitis B virus(HBV) was *** adverse events in mothers and infants during pregnancy and the perinatal period and the HBV motherto-infant transmission blocking rate were compared with the ***:Among the 92 pregnant women,spontaneous abortions occurred in 11 cases,while 3 mothers had a second pregnancy after the initial abortion;72 mothers delivered 73 live infants,of whom 68 infants were followed up for no less than 6 mo,and 12 mothers were still *** pregnancy,the main maternal adverse events were vaginitis(12/72,16.7%),spontaneous abortion(11/95,11.6%),and gestational diabetes(6/72,8.3%);only one case had 1-2 degree elevation of the creatine kinase level(195 U/L).During the perinatal period,the main maternal adverse events were premature rupture of the membranes(8/72,11.1%),preterm delivery(5/72,6.9%),and meconium staining of the amniotic fluid(4/72,5.6%).In addition,2 infants were found to have congenital abnormalities;1 had a scalp hemangioma that did not change in size until 7 mo,and the other had early cerebral palsy,but with rehabilitation training,the infant's motor functions became totally normal at 2 years of

关键词： Pregnancy Chronic hepatitis B Lamivu-dine Safety Hepatitis B virus

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Non-destructive Evaluation of Composite Pressure Vessel by Using FBG Sensors

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Chinese Journal of Aeronautics 2007年第2期20卷 120-123页

作者： hao Jun-cai LENG Jin-song WEI Zhang Center for Composite Materials and Structures Harbin Institute of Technology Harbin 150080 China Harbin Aviation lndustry Co. LTD Harbin 150080 China

In recent years, advanced composite structures are used extensively in many industries such as aerospace, aircraft, automobile, pipeline and civil engineering. Reliability and safety are crucial requirements posed by them to the advanced composite structures be- cause of their harsh working conditions. Therefore, as a very important measure, structural health monitoring （SHM） in-service is deft- nitely demanded for ensuring their safe working in-situ. In this paper, fiber Bragg grating （FBG） sensors are surface-mounted on the hoop and in the axial directions of a FRP pressure vessel to monitor the strain status during its pressurization. The experimental results show that the FBG sensors could be used to monitor the strain development and determine the ultimate failure strain of the composite pressure vessel.

关键词： fiber optic sensor fiber Bragg grating composite pressure vessel non-destructive evaluation

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Global stability of bistable traveling wavefronts for a three-species Lotka-Volterra competition system with nonlocal dispersal

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International Journal of Biomathematics 2023年第5期16卷 87-110页

作者： Yu-cai hao Guo-Bao Zhang College of Mathematics and Statistics Northwest Normal University Lanzhou Gansu 730070P.R.China

This paper is devoted to the study of traveling wavefronts for a three-component Lotka-Volterra system with nonlocal *** system arises in the study of three-species competition model in which there is no competition between two of these three *** has been shown that this system admits a bistable traveling *** this paper,we further investigate the stability of bistable traveling *** constructing suitable super-and sub-solutions and using a dynamical system approach,we obtain the globally asymptotic stability of the bistable traveling wavefronts.

关键词： Three-species competition system nonlocal dispersal bistable traveling wavefronts global stability uniqueness

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Association of serum pepsinogen with degree of gastric mucosal atrophy in an asymptomatic population

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World Journal of Clinical Cases 2021年第31期9卷 9431-9439页

作者： hao-Lei cai Yu-Ling Tong Department of Surgery The Second Affiliated Hospital of Zhejiang University School of MedicineHangzhou 310009Zhejiang ProvinceChina International Healthcare Center The Second Affiliated Hospital of Zhejiang University School of MedicineHangzhou 310009Zhejiang ProvinceChina

BACKGROUND Atrophic gastritis is a precancerous lesion of the *** has been reported that pepsinogen(PG)can reflect the morphology and function of the gastric mucosa,and it is therefore used as a marker for the early diagnosis of atrophic *** To evaluate the diagnostic value of serum PG for degree of gastric mucosal atrophy in asymptomatic Chinese upon physical *** Medical data were collected from subjects who underwent transnasal gastroscopy between October 2016 and October *** each study subject,serum PG levels and presence of Helicobacter pylori(***)infection were *** was evaluated using the Operative Link for Gastritis Assessment(OLGA)classification and Operative Link on Gastric Intestinal Metaplasia Assessment(OLGIM)*** statistical analyses were carried out using SPSS statistical *** A total of 2256 subjects were enrolled and 1922 cases were finally included in the *** on the OLGA grading system,the levels of PGI were slightly decreased,while those of PGII were slightly *** PGI/PGII ratio(PGR)was reduced with increasing *** association between PG and OLGA grading was higher compared with that between PG and the OLGIM grading *** with the OLGA-0 group,a statistically significant difference was observed in the mean age of OLGA-Ⅰ,Ⅲ,and Ⅳ groups(P<0.05).In the ***-positive subjects,the PGR levels were notably lower in the OLGA-Ⅰ,Ⅱ,and Ⅲ groups compared with the OLGA-0 group(P<0.05).***-positive subjects exhibited significantly higher PGI and PGII serum levels and a significantly lower PGR compared with ***-negative patients in different OLGA groups(P<0.05).CONCLUSION Serum PG levels may represent a non-invasive screening marker for gastric mucosal atrophy in asymptomatic subjects.

关键词： Pepsinogen Helicobacter pylori Operative Link for Gastritis Assessment Atrophic gastritis Gastric mucosal atrophy Biomarker

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Electrochemical behavior of 304 stainless steel with electrodeposited niobium as PEMFC bipolar plates

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International Journal of Minerals,Metallurgy and Materials 2012年第4期19卷 328-332页

作者： Cheng-hao Liang cai-hong Cao Nai-bao Huang Transportation Equipments and Ocean Engineering College Dalian Maritime University Dalian 116026 China

In order to enhance the corrosion resistance of 304 stainless steel, niobium was electrodeposited on its surface in air- and water-stable ionic liquids. The electrochemical behaviors of bare and niobium-coated 304 stainless steel were evaluated by electrochemical tests in a simulated proton exchange membrane fuel cell （PEMFC） environment. The results showed that niobium could be electrodeposited on the surface of 304 stainless steel from ionic liquids, and a smooth and strong chemical inert compound film was obtained on the surface of 304 stainless steel, which was mainly composed of NbO and Nb2Os. The thin composite film acted as a barrier and remarkably improved the corrosion resistance of 304 stainless steel in the PEMFC environment.

关键词： proton exchange membrane fuel cells electrodeposition niobium ionic liquids stainless steel corrosion resistance

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Non-normal Hasemann Boundary Value Problem

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Wuhan University Journal of Natural Sciences 2001年第3期6卷 649-651页

作者： cai hao-tao Du Jin-yuan Coll. of Mathematics and Statistics Wuhan University Wuhan 430072 China

We will discuss the non-normal Hasemann boundary value problem: we may find these results are coincided with those of normal Hasemann boundary value problem and non-normal Riemann boundary value problem.

关键词： non-normal positive transformation canonical function

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