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Integration of aspect and slope in snowmelt runoff modeling in a mountain watershed

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Water Science and Engineering 2016年第4期9卷 265-273页

作者： Shalamu Abudu zhu-ping sheng Chun-liang Cui Muatter Saydi Hamed-Zamani Sabzi James Phillip King Texas A&M AgriLife Research and Extension Center at El Paso El Paso TX 79927-5020 USA Xinjiang Water Resources Research Institute Urumqi 830049 China Civil Engineering Department New Mexico State University Las Cruces NM 88003-8006 USA

This study assessed the performances of the traditional temperature-index snowmelt runoff model(SRM) and an SRM model with a finer zonation based on aspect and slope(SRM + AS model) in a data-scarce mountain watershed in the Urumqi River Basin,in Northwest *** proposed SRM + AS model was used to estimate the melt rate with the degree-day factor(DDF) through the division of watershed elevation zones based on aspect and *** simulation results of the SRM + AS model were compared with those of the traditional SRM model to identify the improvements of the SRM + AS model's performance with consideration of topographic features of the *** results show that the performance of the SRM + AS model has improved slightly compared to that of the SRM *** coefficients of determination increased from 0.73,0.69,and 0.79 with the SRM model to 0.76,0.76,and 0.81 with the SRM + AS model during the simulation and validation periods in 2005,2006,and 2007,*** proposed SRM + AS model that considers aspect and slope can improve the accuracy of snowmelt runoff simulation compared to the traditional SRM model in mountain watersheds in arid regions by proper parameterization,careful input data selection,and data preparation.

关键词： Snowmelt runoff model (SRM) Degree-day factor (DDF) Aspect and slope Snow cover area Temperature Precipitation

Complex geometric modeling and tooth contact analysis of a helical face gear pair with arc-tooth

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Journal of Central South University 2022年第4期29卷 1213-1225页

作者： MO Shuai SONG Wen-hao zhu sheng-ping FENG Zhi-you TANG Wen-jie GAO Han-jun School of Mechanical Engineering Tiangong UniversityTianjin 300387China Tianjin Key Laboratory of Modern Electromechanical Equipment Technology Tianjin 300387China State Key Laboratory of Digital Manufacturing Equipment and Technology Huazhong University of Science and TechnologyWuhan 430074China The State Key Laboratory of Virtual Reality Technology and Systems Beijing University of Aeronautics and AstronauticsBeijing 100083China

A complex geometric modeling method of a helical face gear pair with arc-tooth generated by an arc-profile cutting(APC)disc is proposed,and its tooth contact characteristics are ***,the spatial coordinate system of an APC face gear pair is established based on meshing *** the coordinate transformation matrix and the tooth profile of the cutter,the equations of the curve envelope of the APC face gear pair are *** the surface equations are solved to extract the point clouds data by programming in MATLAB,which contains the work surface and the fillet surface of the APC face gear *** the complex geometric model of the APC face gear pair is built by fitting its point *** last,through the analysis of the tooth surface contact,the sensitivity of the APC face gear to the different types of mounting errors is *** results show that the APC face gear pair is the most sensitive to mounting errors in the tooth thickness direction,and it should be strictly controlled in the actual application.

关键词： arc-tooth face gear complex geometric modeling point clouds mounting errors tooth contact analysis

High-intensity focused ultrasound treatment for patients with unresectable pancreatic cancer

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Hepatobiliary & Pancreatic Diseases International 2012年第6期11卷 655-660页

作者： Peng-Zhou Li, Shai-Hong zhu, Wei He, Li-Yong zhu, sheng-ping Liu, Yan Liu, Guo-Hui Wang, Fei Ye Department of General Surgery ,Department of Radiology, Third Xiangya Hospital, Central South University, Changsha 410013, China Department of General Surgery Third Xiangya Hospital Central South University Changsha 410013 China Department of Radiology Third Xiangya Hospital Central South University Changsha 410013 China

BACKGROUND: High-intensity focused ultrasound (HIFU) is a non-invasive method of solid tissue ablation therapy. However, only a few studies have reported the effect of HIFU for unresectable pancreatic cancer. This study aimed to evaluate the clinical benefits, survival time and complications associated with the use of HIFU ablation in patients with unresectable pancreatic cancer. METHODS: Twenty-five patients with unresectable pancreatic cancer were enrolled in our study. All patients received HIFU therapy for tumors at least once. The therapeutic effects of HIFU was evaluated in terms of Karnofsky performance status (KPS) scores, pain relief, serum CA19-9, and imaging by B-US and CT before and after the therapy. We also recorded median overall survival time and complications caused by the treatment. RESULTS: In the 25 patients, KPS scores were above 60, and increased KPS was observed in 23 patients after treatment. Pain relief occurred in 23 patients. Serum CA19-9 levels were significantly reduced one month after HIFU treatment and became negative in 5 patients. B-US revealed enhanced tumor echogenicity in 13 patients and decreased tumor blood supply in 9. Tumor necrosis was confirmed by CT in 8 patients one month after HIFU treatment. The median overall survival time was 10 months, and the 1-year survival rate was 42%. No severe complications were observed after HIFU treatment. CONCLUSION: HIFU can effectively relieve pain, increase KPS, decrease tumor growth and prolong the survival time of patients with unresectable pancreatic cancer.

关键词： pancreatic cancer high-intensity focused ultrasound therapy

Chain Extender-induced Hydrogen Bonding Organization Determines the Morphology and Properties of Thermoplastic Polycarbonate Polyurethane

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Chinese Journal of Polymer Science 2024年第1期42卷 87-96,I0009页

作者： Yi-Lang Qin ping zhu Chen-Xi Ouyang Xia Dong Fuwai Hospital Chinese Academyof Medical Sciences&Peking Union Medical College/National Center for Cardiovascular DiseasesBejing 100037China CASKey Laboratoryof Engineering Plastics CAS Research/Education Centerfor Excellence in Molecular SciencesInstitute ofChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

Thermoplastic polycarbonate polyurethanes(PCUs) are multiblock copolymers that have been applied for medical devices for long time. Aliphatic diols are common chain extenders(CE) involved in the composition of the hard segments of PCU. However, limited knowledge was discovered about how the chemical structure of CE affects the hydrogen bonding organization within PCUs and their mechanical *** investigate this problem, a group of PCUs were synthesized respectively by extending the polymer chain with 1,4-butanediol(BDO),aminoethanol(MEA), ethanediol(EO) as three kinds of chain extenders. Tiny differences in the CE chemical structure results in remarkable variations in phase separation, condensed morphologies, thermal and mechanical properties, which are characterized by Fourier transform infrared spectrometer, atomic force microscopy, small-angle X-ray scattering, differential scanning calorimetry, and tensile tests. The microstructural evolution during unilateral deformation and the different mechanism induced by the different CEs was probed and unveil by in situ wide-and small-angle X-ray diffraction. Symmetry of CE can improve the organization of the hydrogen bonding. The coherence strength of the urethane/urea group also plays a key role by comparing the two PCUs with ethanediol and aminoethanol.

关键词： Thermoplastic polycarbonate polyurethane Chain extender Hydrogen bonding Mechanical properties

3D robust anisotropic diffusion filtering algorithm for sparse view neutron computed tomography 3D image reconstruction

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Nuclear Science and Techniques 2024年第3期35卷 13-29页

作者： Yang Liu Teng-Fei zhu Zhi Luo Xiao-ping Ouyang School of Nuclear Science and Engineering North China Electric Power UniversityBeijing 102206China State Key Laboratory of Nuclear Resources and Environment East China University of TechnologyNanchang 330013China State Key Laboratory of Intense Pulsed Radiation Simulation and Effect Xi’an 710024China

The most critical part of a neutron computed tomography(NCT) system is the image processing algorithm,which directly affects the quality and speed of the reconstructed *** types of noise in the system can degrade the quality of the reconstructed ***,to improve the quality of the reconstructed images of NCT systems,efficient image processing algorithms must be *** anisotropic diffusion filtering(ADF) algorithm can not only effectively suppress the noise in the projection data,but also preserve the image edge structure information by reducing the diffusion at the image ***,we propose the application of the ADF algorithm for NCT image *** compare the performance of different algorithms in NCT systems,we reconstructed images using the ordered subset simultaneous algebraic reconstruction technique(OS-SART) algorithm with different regular terms as image processing *** the iterative reconstruction,we selected two image processing algorithms,the Total Variation and split Bregman solved total variation algorithms,for comparison with the performance of the ADF ***,the filtered back-projection algorithm was used for comparison with an iterative *** reconstructing the projection data of the numerical and clock models,we compared and analyzed the effects of each algorithm applied in the NCT *** on the reconstruction results,OS-SART-ADF outperformed the other algorithms in terms of denoising,preserving the edge structure,and suppressing *** example,when the 3D Shepp–Logan was reconstructed at 25 views,the root mean square error of OS-SART-ADF was the smallest among the four iterative algorithms,at only *** universal quality index,mean structural similarity,and correlation coefficient of the reconstructed image were the largest among all algorithms,with values of 0.9877,0.9878,and 0.9887,respectively.

关键词： NCT OS-SART Sparse-view Anisotropic diffusion filtering

Sparse-view neutron CT 3D image reconstruction algorithm based on split Bregman method

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NUCLEAR SCIENCE AND TECHNIQUES 2024年第9期35卷 1-15页

作者： zhu, Teng-Fei Liu, Yang Luo, Zhi Ouyang, Xiao-ping North China Elect Power Univ Sch Nucl Sci & Engn Beijing 102206 Peoples R China East China Univ Technol State Key Lab Nucl Resources & Environm Nanchang 330013 Peoples R China State Key Lab Intense Pulsed Radiat Simulat & Effe Xian 710024 Peoples R China

As a complement to X-ray computed tomography (CT), neutron tomography has been extensively used in nuclear engineering, materials science, cultural heritage, and industrial applications. Reconstruction of the attenuation matrix for neutron tomography with a traditional analytical algorithm requires hundreds of projection views in the range of 0 degrees to 180 degrees and typically takes several hours to complete. Such a low time-resolved resolution degrades the quality of neutron imaging. Decreasing the number of projection acquisitions is an important approach to improve the time resolution of images; however, this requires efficient reconstruction algorithms. Therefore, sparse-view reconstruction algorithms in neutron tomography need to be investigated. In this study, we investigated the three-dimensional reconstruction algorithm for sparse-view neutron CT scans. To enhance the reconstructed image quality of neutron CT, we propose an algorithm that uses OS-SART to reconstruct images and a split Bregman to solve for the total variation (SBTV). A comparative analysis of the performances of each reconstruction algorithm was performed using simulated and actual experimental data. According to the analyzed results, OS-SART-SBTV is superior to the other algorithms in terms of denoising, suppressing artifacts, and preserving detailed structural information of images.

关键词： Neutron CT OS-SART Sparse-view 3D reconstruction Split Bregman Total variation ALGEBRAIC RECONSTRUCTION 2-PHASE FLOW BEAM ART

Advancements in S-scheme heterojunction materials for photocatalytic environmental remediation

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Journal of Materials Science & Technology 2024年第2期169卷 182-198页

作者： Changliang Nie Xiaohan Wang ping Lu Yukun zhu Xin Li Hua Tang School of Environmental Science and Engineering State Key Laboratory of Bio-fibers and Eco-textilesQingdao UniversityQingdao266071China Institute of Biomass Engineering Key Laboratory of Energy Plants Resource and UtilizationMinistry of Agriculture and Rural AffairsSouth China Agricultural UniversityGuangzhou510642China School of Environmental Science and Engineering Shandong UniversityQingdao266237China

Recently,S-scheme heterojunctions have gained considerable attention in the field of photocatalytic environmental remediation as their potential to achieve efficient spatial charge separation coupled with strong redox ***,this review provides an overview of the current state-of-the-art in the development of S-scheme-based photocatalysts for the purification of environmental *** review first covers the fundamentals of heterogeneous photocatalysis for environmental ***,an introduction to the background,mechanism,design principles,and characterization techniques of S-scheme heterojunctions is ***,the review presents a comparison and summary of using various S-scheme photocatalysts for the removal of several target pollutants,such as bacteria,heavy metals,nitrogen oxides,antibiotics,and ***,the modification strategies of S-scheme heterojunction photocatalysts are also ***,a brief discussion of the challenges and prospects associated with S-scheme photocatalytic systems is demonstrated.

关键词： S-scheme heterojunctions Photocatalyst Pollutant Environmental remediation

Poly(3-hexylthio) thiophene Field-effect Transistor Device Performance: Impact of the Content of Hexylthio Side Chain on Backbone

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Chinese Journal of Polymer Science 2024年第1期42卷 14-23,I0005页

作者： Hao-Yu Liu Lian-He Han Ling-Wei Kong Li-ping zhu Xiao-Lan Qiao Mei-Fang zhu State Key Laboratory for Modification of Chemical Fibers and Polymer Materials College of Materials Science and EngineeringDonghua UniversityShanghai 201620China School of Electronic Information and Electrical Engineering Shanghai Jiao Tong UniversityShanghai 200240China

Regioregular poly(3-hexylthio)thiopene(P3HTT) has emerged tremendous potential in organic electronic applications due to the strong noncovalent interactions from the sulfur atom linked to thiophene. However, P3HTT generally exhibits low charge mobility mostly due to poor solution processability attributed to dense arrangement of hexylthio side chain in polymer, which led to strong noncovalent interactions among sulfur atoms. To balance the nonvalent interaction and aggregation for P3HTT, herein, we systematically study the effect of hexylthio side chain content in polymer backbone on the structure and properties. A series of regioregular P3HTT-based homopolymers(P3HTT, P3HTT-50,P3HTT-33 and P3HTT-25) were prepared via Kumada catalyst transfer polycondensation method from a set of mono-, bi-, ter-and quarterthiophenes containing different contents of hexylthio side chain. The DFT calculation shows the planarity of polymers backbone could be improved through reducing the density of hexylthio side chain in polymer mainchain. And significant changes in their crystallinity, aggregation and optical properties were observed with the content of hexylthio side chain reducing. The P3HTT-33 displayed the highest field-effect transistor hole mobility of 2.83×10^(-2) cm^(2)·V^(-1)·s^(-1) resulting from a balance between the crystallinity and planarity. This study demonstrates modulating the content of hexylthio side chain in P3HTT is an effective strategy to optimize the opto-electronic properties of polymer obtaining excellent semiconductor device performance.

关键词： Conjugated polymer Polythiophene Noncovalent interaction Molecular aggregation Organic field-effect transistor

A case of solitary choroidal tuberculoma with highly positive tuberculin skin test and negative interferon gamma release assays

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International Journal of Ophthalmology(English edition) 2024年第5期17卷 969-972页

作者： Lin Zhou Bin Hu zhu-ping Xu Department of Ophthalmology Sichuan Provincial People’s HospitalUniversity of Electronic Science and Technology of ChinaChengdu 610072Sichuan ProvinceChina Department of Ophthalmology Chengdu Tianfu New District People’s HospitalChengdu 641400Sichuan ProvinceChina Department of Ophthalmology West China HospitalSichuan UniversityChengdu 610041Sichuan ProvinceChina

Dear Editor,Tuberculosis(TB)is an infectious disease which has been considered as a global public health emergency problem during the past *** World Health Organization has estimated that approximately one-third of the world’s population are infected by ***,only 10%of patients with TB is *** can affect multiple organs throughout the *** percent of those infected are pulmonary *** TB can occur with or without lung or other systemic *** is a rare extrapulmonary form of the disease and occupied about 3.5%–5%of all of the *** should not be disregarded as its potential influence on vision *** intraocular and/or extraocular structures could be impacted by ocular TB[1].Uvea was the most common affected structure[2].

关键词： organs ocular infected