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Science China(Technological Sciences) 2011年第6期54卷 1568-1574页

作者： hu HongChang TIAN FuQiang hu heping Department of Hydraulic Engineering State Key Laboratory of Hydroscience and Engineering Tsinghua University Beijing 100084 China

Soil particle size distribution(PSD),one of the most important soil physical attributes,is of great importance to soil water movement,soil erosion and soil solute *** this study,the soil PSD of 563 soil samples from the mulched drip irrigated cotton fields in Xinjiang of China were measured by laser diffraction particle size *** soil PSD characteristics and its relations with soil water and salt were studied by using the combined methods of textural triangle,fractal and multifractal *** results showed very low clay content(about 1.52%) while really high sand content of the studied soil,and a complex shape of bimodal or unimodal of soil *** results also showed that the two indices,i.e.,standard deviation and the peak value of soil particle relative volumes,were good indicators of soil PSD and thus had good relations with fractal and multifractal *** correlative analysis further indicated that the mulched drip irrigation had a significant impact on the distribution of the soil salt,while this impact withered for the deeper soil *** soil texture feature was found to dominate soil water and salt distribution,especially the surface soil salt content and the deep soil water content.

关键词： soil particle size distribution soil water and salt mulched drip irrigation fractal analysis multifractal analysis textural triangle

Characteristics of soil water retention curve at macro-scale

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Science China(Technological Sciences) 2009年第10期52卷 2990-2996页

作者： TIAN FuQiang MOU LiQin hu heping State Key Laboratory of Hydro-Science and Engineering Department of Hydraulic EngineeringTsinghua UniversityBeijing 100084China

Scale adaptable hydrological models have attracted more and more attentions in the hydrological modeling research community, and the constitutive relationship at the macro-scale is one of the most important issues, upon which there are not enough research activities yet. Taking the constitutive relationships of soil water movement--soil water retention curve (SWRC) as an example, this study extends the definition of SWRC at the micro-scale to that at the macro-scale, and aided by Monte Carlo method we demonstrate that soil property and the spatial distribution of soil moisture will affect the features of SWRC greatly. Furthermore, we assume that the spatial distribution of soil moisture is the result of self-organization of climate, soil, ground water and soil water movement under the specific boundary conditions, and we also carry out numerical experiments of soil water movement at the vertical direction in order to explore the relationship between SWRC at the macro-scale and the combinations of climate, soil, and groundwater. The results show that SWRCs at the macro-scale and micro-scale presents totally different features, e.g., the essential hysteresis phenomenon which is exaggerated with increasing aridity index and rising groundwater table. Soil property plays an important role in the shape of SWRC which will even lead to a rectangular shape under drier conditions, and power function form of SWRC widely adopted in hydrological model might be revised for most situations at the macro-scale.

关键词： scale issue constitutive relationship soil water retention curve Richards equation

A two-dimensional Richards equation solver based on CVODE for variably saturated soil water movement

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Science China(Technological Sciences) 2011年第12期54卷 3251-3264页

作者： TIAN FuQiang GAO Long hu heping Department of Hydraulic Engineering State Key Laboratory of Hydroscience and Engineering Tsinghua University Beijing 100084 China Development Research Center Ministry of Water Resources of China Beijing 100038 China

A numerical model of two-dimensional soil water movement under surface drip irrigation condition was developed. The physical process of soil water movement is described by 2D Richards equation,and the upper boundary condition is depicted by the improved moving ponded area boundary. The partial differential equation(PDE) is transformed into ordinary differential equations(ODEs) through spatial semi-discretization and numerically solved by an ordinary differential equation solver(CVODE) . The numerical and field experiments indicate the good performance of the model in terms of accuracy and efficiency. The model provides a useful tool for long-term simulation of soil water movement under surface drip irrigation. Also,the model can serve as a general 2D Richards equation solver for variably saturated soil water movement,which is named as TIVS model(Tsinghua Integrated Variably Saturated soil water movement model).

关键词： surface drip irrigation moving ponded area boundary CVODE Richards equation

Spatial averaging infiltration model for layered soil

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Science China(Technological Sciences) 2009年第4期52卷 1050-1058页

作者： heping hu ZhiYong Yang FuQiang Tian Department of Hydraulic Engineering State Key Laboratory of Hydroscience and Engineering Tsinghua University Beijing 100084 China Department of Water Resources Institute of Water Resources and Hydropower Research Beijing 100038 China

To quantify the influences of soil heterogeneity on infiltration, a spatial averaging infiltration model for layered soil (SAI model) is developed by coupling the spatial averaging approach proposed by Chen et al. and the Generalized Green-Ampt model proposed by Jia et al. In the SAI model, the spatial hetero- geneity along the horizontal direction is described by a probability distribution function, while that along the vertical direction is represented by the layered soils. The SAI model is tested on a typical soil using Monte Carlo simulations as the base model. The results show that the SAI model can directly incorporate the influence of spatial heterogeneity on infiltration on the macro scale. It is also found that the homogeneous assumption of soil hydraulic conductivity along the horizontal direction will overes- timate the infiltration rate, while that along the vertical direction will underestimate the infiltration rate significantly during rainstorm periods. The SAI model is adopted in the spatial averaging hydrological model developed by the authors, and the results prove that it can be applied in the macro-scale hy- drological and land surface process modeling in a promising way.

关键词： infiltration heterogeneity spatial averaging Green-Ampt model

Thermodynamic watershed hydrological model: Constitutive relationship

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Science China(Technological Sciences) 2008年第9期51卷 1353-1369页

作者： TIAN FuQiang hu heping LEI ZhiDong State Key Laboratory of Hydroscience and Engineering Department of Hydraulic EngineeringTsinghua UniversityBeijing 100084China

The representative elementary watershed (REW) approach proposed by Reggiani et al. was the first attempt to develop scale adaptable equations applicable directly at the macro scale. Tian et al. extended the initial definition of REW for simulating the energy related processes, and re-organized the deriving procedure of balance equations so that additional sub-regions and substances could be easily incorpo-rated. The resultant ordinary differential equation set can simulate various hydro-logical processes in a physically reasonable way. However, constitutive and geo-metric relationships have not been developed for Tian et al.'s equation set, which are necessary for the thermodynamic watershed hydrological model to apply in hydrological modeling practice. In this work, the constitutive equations for mass exchange terms and momentum exchange terms were developed as well as geo-metric relationships. The closed ordinary differential equation set with nine equa-tions was finally obtained.

关键词： thermodynamics hydrological model constitutive relationship thermodynamic watershed hydrological model representative elementary watershed

Analysis of the effect of regional lateral inflow on the flood peak of the Three Gorges Reservoir

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Science China(Technological Sciences) 2011年第4期54卷 914-923页

作者： WANG BaiWei TIAN FuQiang hu heping State Key Laboratory of Hydroscience and Engineering Department of Hydraulic EngineeringTsinghua UniversityBeijing 100084China

The Three Gorges Region(TGR),located at the lower reach of the Upper Yangtze River Basin(UYRB) in China,suffers from heavy rainstorm *** runoff generated from TGR composes an important part of the total flood at the famous Three Gorges Reservoir(TGRe).During the severe flood period in 1954,for example,the water from TGR accounted for up to 13.2% of the 30-days maximum flood volume of the *** the short and steep tributaries with rapid concentration,the regional lateral inflow(RLI) may induce more serious effect on the flood peak of the TGRe than the ***,hydrological data of the sparse gauge stations is too insufficient to evaluate the effect of *** paper studied the impact by analyzing 880 flood events during *** comparing the observed hydrograph and simulated hydrograph with HEC-RAS software regarding no RLI,the effect of RLI on flood peak value and timing properties was identified and *** variability of this effect among floods of different magnitudes was also *** evaluate the analysis uncertainty associated with the parameter of roughness coefficient,four sets of roughness coefficients from different research groups were employed in this *** results showed that RLI contributes discharge of 3524 m3/s to flood peaks of the TGRe on average,with the contribution ratio of 15.9%.RLI contributes 12000 m3/s to the flood peaks larger than 50000 m3/s on average,with 25000 m3/s as its upper bound,while the contribution ratio can reach up to 50%,with an average of 20%.The variability of this effect is great among different *** analysis showed that to larger flood peak of the TGRe,RLI contributes more discharge with higher variability,and the contribution ratio and its variability are slightly larger,and events with higher contribution ratio occur more *** can reshape the hydrograph,leading to earlier appearance of flood *** effect and its variability increase with the con

关键词： regional lateral inflow flood peak flood peak time HEC-RAS the Three Gorges

Chemo–immunotherapy for chemo-resistance and metastasis of triple-negative breast cancer by combination of iron-oxide nanoparticles and dual-targeting doxorubicin liposomes

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Chinese Chemical Letters 2023年第10期34卷 76-81页

作者： heping hu Lijia Yu Zhao Ding Jinsong Ding Yiguo hu Zongning Yin Key Laboratory of Drug Targeting and Drug Delivery System of Ministry of Education West China School of PharmacySichuan UniversityChengdu 610041China Sichuan huiyu Seacross Medical Technology Co. Ltd.Chengdu 610031China Sichuan huiyu Pharmaceutical Co. Ltd.Neijiang 641000China Xiangya School of Pharmaceutical Sciences Central South UniversityChangsha 410013China State Key Laboratory of Biotherapy and Cancer Center West China HospitalSichuan Universityand Collaborative Innovation Center for BiotherapyChengdu 610044China

Triple-negative breast cancer(TNBC)lacks specific regimens for targeted *** chemotherapy promotes the evolution of TNBC into highly chemo-resistant tumors that metastasize to multiple organs ***,polyacrylic acid-coated ultrasmall superparamagnetic iron-oxide nanoparticles(PAA@IONs)and dual-targeting doxorubicin liposomes achieved chemo–immunotherapy through intermittent *** inhibited tumor-drug resistance and multiorgan-specific metastasis significantly by targeting tumors and the *** deciphered an immunosuppressive pre-metastatic niche and discovered that PAA@IONs could target tumors,tumor-draining lymph nodes(TDLNs),the liver,bone,and *** promoted the polarization of macrophages into M1 macrophages in these organs and *** action remodeled the immunosuppressive microenvironment and induced a sustained immune response,thereby reducing organ-specific *** the disadvantages of doxorubicin-induced cardiotoxicity as well as low tumor specificity,dual peptide-modified liposomes could target CD206 and CD13 simultaneously,and reverse *** properties resulted in a significant decrease in the numbers of myeloid-derived suppressor cells(MDSCs)and cancer stem cells(CSCs)in the liver,lungs,and bone,thereby reducing protein expression of Ki-67 in TDLNs,and dramatically increasing the number of cluster of differentiation(CD)8+T cells and CD8+T cell/T-regulatory-cell ratio in tumors and TDLNs(P<0.0001).Compared with the control(P<0.05 and P<0.01,respectively)or free drug(P<0.0001 and P<0.01,respectively),multi-organ metastases were suppressed significantly,tumor-growth rate reduced,and survival *** drug-delivery system overcame TNBC chemo-resistance and inhibited multiorgan-specific *** circumvents the lack of effective therapeutic targets,the problem of patient selection due to a low mutation rate,and can simultaneously offer the possibility of avoid

关键词： Multidrug resistance Multiorgan-specific metastases Immunogenic cell death Intermittent dosing Immunosuppressive tumor microenvironment Tumor-associated macrophages

Dynamically Authorized Role-Based Access Control for Grid Applications

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Geo-Spatial Information Science 2006年第3期9卷 223-228,233页

作者： YAO Hanbing hu heping LU Zhengding LI Ruixuan College of Computer Science and Technology Huazhong University of Science and Technology Guanshan Wuhan 430074 China

Grid computing is concerned with the sharing and coordinated use of diverse resources in distributed “virtual organizations”. The heterogeneous, dynamic and multi-domain nature of these environments makes challenging security issues that demand new technical approaches. Despite the recent advances in access control approaches applicable to Grid computing, there remain issues that impede the development of effective access control models for Grid applications. Among them there are the lack of context-based models for access control, and reliance on identity or capability-based access control schemes. An access control scheme that resolve these issues is presented, and a dynamically authorized role-based access control (D-RBAC) model extending the RBAC with context constraints is proposed. The D-RABC mechanisms dynamically grant permissions to users based on a set of contextual information collected from the system and user’s environments, while retaining the advantages of RBAC model. The implementation architecture of D-RBAC for the Grid application is also described.

关键词： Grid security RBAC context-based access control

Measurements of ^(134)Cs and ^(137)Cs in urine and estimation of the internal dose of an adult exposed to the Chernobyl Accident

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Nuclear Science and Techniques 2007年第2期18卷 115-117页

作者： ZHAO Shuquan huANG Shibin LIU Shiming hu heping WU Mingyu XIANG Xiqiao Zhu Guoying Institute of Radiation Medicine Fudan University Shanghai 200032 China Shanghai Medical College Fudan University Shanghai 200032 China Jinan Maritime Safety Administration of China Jinan 250062 China

To estimate the internal dose of a Chinese visiting scholar internally contaminated because of the Cherno- byl Accident, the contents of 134Cs and 137Cs in urine were measured using a Ge(Li) γ-spectrometer. The internal doses were calculated based on data from the ICRP Publications. The effective doses from 134Cs and 137Cs were estimated to be 61 μSv and 98 μ Sv, respectively. The sum of 159 μSv was lower than the total effective dose (310 μSv), from the inhalation and ingestion of natural radionuclides. The dose of 131I was also reviewed referring to the UNSCEAR 2000 Report. The equivalent effective dose of 131I was estimated to be 2.9 mSv, 18 times more than the amount of 134Cs and 137Cs. Therefore, it is considered that the earlier estimation of internal doses of 131I is important in evaluating radiation injuries from a nuclear reactor accident.

关键词：切尔诺贝利核事故成年人内照射剂量估计尿液铯134 铯137 光谱测定

Differences in changes of potential evaporation in the mountainous and oasis regions of the Tarim basin, northwest China

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Science China(Technological Sciences) 2009年第8期52卷 1981-1989页

作者： HAN SongJun hu heping YANG DaWen LIU QunChang Department of Irrigation and Drainage China Institute of Water Resources and Hydropower ResearchBeijing 100044China State Key Laboratory of Hydro-Science and Engineering Department of Hydraulic EngineeringTsinghua UniversityBeijing 100084China

Data from eleven meteorological stations in the Tianshan mountains and the north slope of west Kunlun mountains, and eighteen meteorological stations in the Kaidu-Kongque river, Akesu river, Kashiger river and Yankant river oases were examined to assess the differences in changes in potential evaporation from 1960 to 2006 in the mountainous and oasis regions of the Tarim basin and the relationships of these changes to meteorological factors. The decreasing trends in potential evaporation were primarily due to the decrease in the aerodynamic terms in both the mountainous and oasis regions, but the trends in the oasis regions were more pronounced. Based on the complementary relationship between potential and actual evaporation, the decreasing trends in potential evaporation appeared to be related to the increasing trends in precipitation in the mountainous regions and the increasing trends in water consumption in the oasis regions, thus reflecting the different impacts of natural changes and anthropogenic influences.

关键词： potential evaporation Tarim basin climate change anthropogenic influence

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