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基于等效面源的大体积箱式废物γ扫描技术研究

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核技术 2025年第2期48卷 64-71页

作者：徐力顾卫国杨桧王德忠上海交通大学机械与动力工程学院上海200240

核设施退役产生的大体积箱型废物核素分布极不均匀,基于传统层析γ扫描(Tomographic Gamma Scanning,TGS)技术对其进行活度测量,误差可达6个数量级,难以安全处置。本研究通过提出新型的γ扫描方法,建立重建算法模型,形成基于等效面源的... 详细信息

核设施退役产生的大体积箱型废物核素分布极不均匀,基于传统层析γ扫描(Tomographic Gamma Scanning,TGS)技术对其进行活度测量,误差可达6个数量级,难以安全处置。本研究通过提出新型的γ扫描方法,建立重建算法模型,形成基于等效面源的改进型层析γ扫描技术(Improved Tomographic Gamma Scanning,ITGS)。该方法基于不同γ扫描位置的计数率比值,计算出废物箱内核素的基本分布,最后结合效率刻度得到精准的活度重建结果。对废物箱内60Co核素不同的放射源分布开展γ扫描实验,发现了核素分布与测量参数对重建结果的影响规律,验证了方法的准确性。模拟测试结果表明:更深入的放射源位置或者更大的介质密度,都会增加活度重建的误差。在相同的测量时间内,ITGS可将测量误差可控制在一个数量级内。该方法通过合理布置测量系统对放射性废物箱进行活度重建,可以在核素分布不均匀以及高密度介质等复杂工况下取得较高的重建精度,减少了废物处置对人类和环境带来的安全隐患。

关键词：层析γ扫描等效面源方法大体积放射性箱体废物

Engineering multiple optimization strategy on bismuth oxyhalide photoactive materials for efficient photoelectrochemical applications

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Wuli Huaxue xuebao/ Acta Physico - Chimica Sinica 2025年第2期41卷 48-80页

作者： Yan, Pengcheng Wang, Peng Huang, Jing Mo, Zhao xu, li Chen, Yun Zhang, Yu Qi, Zhichong xu, Hui li, Henan Institute for Energy Research School of Materials Science and Engineering School of Chemistry and Chemical Engineering Jiangsu University Jiangsu Province Zhenjiang 212013 China

The photoelectrochemical (PEC) technique, as a simple solar energy conversion device, is one of the most promising solutions for addressing both environmental and energy challenges. PEC technique mainly involves the photoconversion process of photoactive materials through carrier excitation and charge transfer under light irradiation, and the active material plays a central role in the entire system. The design and synthesis of highly PEC active materials is crucial for achieving efficient PEC performance. The photoelectric conversion efficiency of photoactive materials mainly depends on broad range of light absorption response and rapid separation/transfer rate of photogenerated carriers. Common photosensitive semiconductors can be used as photoelectric active materials, including metal oxides, metal sulfides, organic small molecules and organic polymers. However, achieving a high photoelectric conversion efficiency is challenging due to the inherent limitations of using a single semiconductor material. Exploring functional composites with specific structural compositions can overcome the performance deficiencies of individual semiconductor materials. In addition, the ultraviolet region of the solar spectrum accounts for only about 5 %, while visible light accounts for approximately 45 %. The development of PEC active materials that can be driven by visible light, such as silver, bismuth, and organic polymer materials, is crucial for the commercial application of PEC technique. Due to the characteristics of bismuth oxyhalide BiOX (X = Cl, Br, I)-based materials, such as an adjustable band gap, a unique layered structure, non-toxicity, a wide light absorption range and outstanding light stability, the PEC technique based on BiOX (X = Cl, Br, I) has become a popular research topic. In this paper, the physicochemical properties of BiOX (X = Cl, Br, I)-based materials are reviewed. The methods used to modify BiOX (X = Cl, Br, I)-based materials from the persp

关键词： Bismuth oxyhalide Charge separation Heterojunction Photoelectrochemical performance Sensor

Stable expression and control parameters in the numerical simulation of unsaturated flow

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Frontiers of Structural and Civil Engineering 2022年第12期16卷 1501-1514页

作者： Zhiyuan ZHANG xu li Yongkang WU Xiaokang li Key Laboratory of Urban Underground Engineering of Ministry of Education Beijing Jiaotong UniversityBeijing 100044China

The Richards’equation describes the flow phenomenon in unsaturated porous media and is essential to hydrology and environmental *** study evaluated the numerical stability of two different forms of the Richards’*** analyses were performed to investigate the control parameters of the *** results show that the h-form Richards’equation has better applicability for calculating variable saturation flows than theθ-form Richards’*** the h-form Richards’equation,the hydraulic conductivity of the soil in the low-suction range and the specific moisture capacity in the high-suction range primarily influenced the *** addition,sensitivity analyses indicated that the saturated hydraulic conductivity,initial condition,and air-entry pressure have a higher sensitivity to the simulation results than the saturated water content,rainfall intensity,and decline rate of hydraulic ***,their correctness needs to be guaranteed first in numerical *** research findings can provide a helpful reference for improving the reliability of numerical simulations of unsaturated flows.

关键词： Richards’equation sensitivity analysis unsaturated soil hydraulic diffusivity seepage simulation

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A dynamic soil freezing characteristic curve model for frozen soil

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第8期16卷 3339-3352页

作者： Xiaokang li xu li Jiankun liu Key Laboratory of Urban Underground Engineering of Ministry of Education Beijing Jiaotong UniversityBeijing100044China School of Civil Engineering Sun Yat-sen UniversityZhuhai519082China

The soil freezing characteristic curve(SFCC)plays a fundamental role in comprehending thermohydraulic behavior and numerical simulation of frozen *** study proposes a dynamic model to uniformly express SFCCs amidst varying total water contents throughout the freezing-thawing ***,a general model is proposed,wherein the unfrozen water content at arbitrary temperature is determined as the lesser of the current total water content and the reference value derived from saturated *** dynamic performance of this model is verified through test ***,in accordance with electric double layer(EDL)theory,the theoretical residual and minimum temperatures in SFCC are calculated to be-14.5℃to-20℃for clay particles and-260℃,*** ensure that the SFCC curve ends at minimum temperature,a correction function is introduced into the general ***,a simplified dynamic model is proposed and investigated,necessitating only three parameters inherited from the general ***,both general and simplified models are evaluated based on a test database and proven to fit the test data exactly across the entire temperature *** recommended parameter values for various types of soils are ***,this study provides not only a theoretical basis for most empirical equations but also proposes a new and more general equation to describe the SFCC.

关键词： Frozen soils Unsaturated soils Soil freezing characteristic curve(SFCC) Mathematic models

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关于共同富裕的五重理论困囿及纾解

石河子大学学报(哲学社会科学版) 2025年第01期39卷 30-36页

作者：李桂花李旭东吉林大学马克思主义学院

扎实推动共同富裕是新时代中国特色社会主义的创新实践，它对经典马克思主义共同富裕理论形成深刻诘问。当下我国共同富裕理论主要面临两极分化存在与否之辩、按劳分配主体地位之谜、智能革命下分配方式之困、“先富带动后富”伦理之争... 详细信息

扎实推动共同富裕是新时代中国特色社会主义的创新实践，它对经典马克思主义共同富裕理论形成深刻诘问。当下我国共同富裕理论主要面临两极分化存在与否之辩、按劳分配主体地位之谜、智能革命下分配方式之困、“先富带动后富”伦理之争、北欧国家福利社会之思五重理论困囿。唯有在尊重实际、立足现实的实践基础和厘定概念、澄清前提的逻辑基础之上，才能客观审视和正确回应这些理论症结，填补行将形成的理论与实践鸿沟，即我国当下存在“相对贫富差距”而无“绝对两极分化”；按劳分配的主体地位应从规范性视角而非描述性视角去把握；“共有”和“共建”的双重分配逻辑是应对智能时代来临的指导分配原则；因继承了新中国成立以来的“三大正外部性”，先富群体天然具有带动后富的伦理责任；高福利制度下的北欧社会属于“自发式”普遍富足而非“自觉式”共同富裕。

关键词：共同富裕理论困囿按劳分配

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On GF(p)-linear complexities of binary sequences

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The Journal of China Universities of Posts and Telecommunications 2009年第4期16卷 112-115,124页

作者： xu li-qing Software Engineering Institute East China Normal University Shanghai 200062 China

Several geometric sequences have very low linear complexities when considered as sequences over GF（p）, such as the binary sequences of period q^n - 1 constructed by Chan and Games [1-2] （q is a prime power p^m, p is an odd prime） with the maximal possible linear complexity q^n-1 when considered as sequences over GF（2）. This indicates that binary sequences with high GF（2） linear complexities LC2 and low GF（p）-linear complexities LCp are not secure for use in stream ciphers. In this article, several lower bounds on the GF（p）-linear complexities of binary sequences is proved and the results are applied to the GF（p）-linear complexities of Blum-Blum-Shub, self-shrinking, and de Bruijn sequences. A lower bound on the number of the binary sequences with LC2 〉 LCD is also presented.

关键词： cryptography stream cipher binary sequences GF(2) linear complexity GF(p)-linear complexity

On Isodual Double Toeplitz Codes

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Journal of Systems Science & Complexity 2024年第5期37卷 2196-2206页

作者： SHI Minjia xu li SOLÉ Patrick Key Laboratory of Intelligent Computing and Signal Processing Ministry of EducationSchool of Mathematical SciencesAnhui UniversityHefei 230601China State Key Laboratory of Information Security Institute of Information EngineeringChinese Academy of SciencesBeijing 100093China CNRS University of Aix MarseilleCentrale MarseilleI2MMarseille 13284France

Double Toeplitz(shortly DT)codes are introduced here as a generalization of double circulant *** authors show that such a code is isodual,hence formally self-dual(FSD).FSD codes form a far-reaching generalization of self-dual codes,the most important class of codes of rate ***-dual DT codes are characterized as double circulant or double ***,even binary DT codes are characterized as double *** examples obtained by exhaustive search show that the codes constructed have best-known minimum distance,up to one unit,amongst formally self-dual codes,and sometimes improve on the known *** q=2,the authors find four improvements on the best-known values of the minimum distance of FSD *** F4 an explicit construction of DT codes,based on quadratic residues in a prime field,performs equally *** authors show that DT codes are asymptotically good over ***,the authors construct DT codes arbitrarily close to the asymptotic Varshamov-Gilbert bound for codes of rate one half.

关键词： Double circulant codes double Toeplitz codes isodual codes formally self-dual codes

Significance of two different ranking methods for studying fish fauna:a case study on the fish fauna from upper and middle portions from Mekong River

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Integrative Zoology 2023年第2期18卷 316-332页

作者： Wei ZHOU xu li Key Laboratory for Conserving Wildlife with Small Populations in Yunnan Southwest Forestry UniversityKunmingChina

Studies onﬁsh fauna should not only focus onﬁsh composition and the comparison ofﬁsh composition among the study region and adjacent regions,but should also explore the origin and uniqueness of different taxa as well as the substitution of genera and *** this study,the value ofﬂoristic presence method was modiﬁed and renamed the value ofﬁsh fauna presence(VFFP)*** speciﬁc steps of the VFFP method and the traditionalﬁsh fauna analysis(TFFA)method were reﬁned and ***,the VFFP and TFFA methods were applied to study theﬁsh fauna of the upper and middle portions of the Mekong River *** results indicate that the TFFA method reﬂects the families(subfamilies)and genera that constitute the main body ofﬁsh in the studied river *** results of the VFFP method show which families(subfamilies)and genera are representative for the ***,combining the TFFA and VFFP methods to analyze the composition ofﬁsh fauna can reﬂect the characteristics ofﬁsh fauna from different *** case study shows that theﬁsh fauna of the Mekong River is a part of theﬁsh fauna of Southeast *** it shows some similarities to the composition of South Asianﬁsh fauna,it does not belong to the South Asianﬁsh fauna as a whole,and is essentially different from the East Asianﬁsh *** study provides an objective,quantitative,and veriﬁable method for studyingﬁsh fauna.

关键词： ﬁsh composition ranking Southeast Asia traditionalﬁsh fauna analysis value ofﬁsh fauna presence

Fabrication of multifunctional polydopamine-coated gold nanobones for PA/CT imaging and enhanced synergistic chemo-photothermal therapy

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Journal of Materials Science & Technology 2021年第4期63卷 97-105页

作者： Jingwei xu Xiaju Cheng Fuxian Chen Weijie li Xiaohui Xiao Puxiang Lai Guopeng xu li xu Yue Pan Department of Cardiothoralic Surgery Suzhou Municipal Hospital InstitutionSuzhou 215002China Jiangsu Key Laboratory of Infection and Immunity Institutes of Biology and Medical SciencesSoochow UniversitySuzhou 215123China Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation Medical Research CenterSun Yat-Sen Memorial HospitalSun Yat-Sen UniversityGuangzhou 510120China Center for Precision Medicine Sun Yat-Sen UniversityGuangzhou 510080China The Hong Kong Polytechnic University Department of Biomedical EngineeringHong Kong SARChina Department of Respiratory Medicine Suzhou Municipal Hospital InstitutionSuzhou 215002China

Multimodal imaging-guided chemo-photothermal therapy is an excellent cancer treatment,which can not only efficiently against tumor,but also can offer precise treatment window and real-time monitoring of the treatment *** our work,polydopamine(PDA)-coated gold nanobones(AuNBs@PDA nanocomplexes)were designed for this *** AuNBs@PDA nanocomplexes have strong absorbance in the near infrared(NIR)region and higher photothermal conversion efficiency(75.48%)than gold nanobones alone,which was facilitated for photoacoustic imaging and photothermal ***,the loading efficiency of doxorubicin(DOX)by AuNBs@PDA nanocomplexes could be up to about 70%and DOX release from AuNBs@PDA/DOX nanocomplexes sensitively response to the lower pH environment and NIR laser irradiation,which makes them become the excellent nano-carrier for the delivery of chemotherapy *** vitro and in vivo studies showed significant cytotoxicity and antitumor efficacy by the AuNBs@PDA/DOX nanoplatform with negligible side ***,the nanoplatform was also successfully employed for computed tomography(CT)imaging,attributing to the high atomic number and high X-ray attenuation coefficient of ***,we believed that the proposed PDA-coated gold nanobones would be a novel multifunctional theranostic nanoagent to realize the PA/CT imaging-guided chemo-photothermal therapy of cancer.

关键词： dopamine treatment bones