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Evidence of temperature-controlled dissolved inorganic nitrogen distribution in a shallow lake

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Journal of Environmental Sciences 2022年第12期34卷 105-114页

作者： Yan wen wenqiang zhang Baoqing Shan jie Qu Research Center for Eco-Environmental Sciences Chinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China

Dissolved inorganic nitrogen(DIN) plays an important role in aquatic ecosystems as an available source of nitrogen(N). Despite recent advances in our understanding of the effects of climate change on DIN in coastal waters, shallow high-latitude lakes exposed to large seasonal temperature differences have received limited research attention. Therefore,in the present study, Baiyangdian Lake(BYDL) was selected as the study area, as a typical high latitude shallow lake in North China. Based on water and sediment samples collected in spring, summer and winter seasons, DIN accumulation in sedimentary pore water and DIN diffusion fluxes at the sediment-water interface were quantified under different temperature conditions. Correlation analysis was used to establish the effects of temperature on DIN concentration and diffusion in different media. Results show that the diffusion of DIN at the lake sediment-water interface exhibited a strongly positive relationship with temperature, suggesting that high temperature conditions lead to greater DIN release from sediments. Cold temperatures cause DIN accumulation in sedimentary pore water, providing sufficient substrate for N-related bacteria in the sediment under cold temperature conditions. Temperature controls the vertical distribution of DIN by affecting its migratory diffusion and transformation at the sediment-water interface. These findings are valuable for understanding the impact of climate change on the distribution of N in inland shallow lakes,especially in high latitude shallow lakes subjected to large seasonal temperature differences throughout the year.

关键词： Shallow lake Temperature Dissolved inorganic nitrogen Vertical distribution Diffusion flux

On the construction of odd-variable boolean functions with optimal algebraic immunity

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The Journal of China Universities of Posts and Telecommunications 2013年第3期20卷 73-77页

作者： zhang jie wen Qiao-yan School of Science Beijing University of Posts and Telecommunications State Key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications

Algebraic immunity is an important cryptographic property of Boolean functions. In this paper, odd-variable balanced Boolean functions with optimal algebraic immunity are obtained by m-sequence and consequently, we get bases with special constructions of vector space. Furthermore, through swapping some vectors of these two bases, we establish all kinds of odd-variable balanced Boolean functions with optimal algebraic immunity.

关键词： algebraic immunity Boolean functions algebraic attacks annihilators

Generalized Polynomial Chaos for Nonlinear Random Pantograph Equations

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Acta Mathematicae Applicatae Sinica 2016年第3期32卷 685-700页

作者： wen-jie SHI Cheng-jian zhang School of mathematics and statistics Huazhong University of Science and Technology School of Mathematics and Computer Science Wuhan Textile University

This paper is concerned with the application of generalized polynomial chaos （gPC） method to nonlinear random pantograph equations. An error estimation of gPC method is derived. The global error analysis is given for the error arising from finite-dimensional noise （FDN） assumption, projection error, aliasing error and discretization error. In the end, with several numerical experiments, the theoretical results are further illustrated.

关键词： generalized polynomial chaos random pantograph equations error estimation finite-dimensional noise

Algebraic immunities of vector-valued functions over finite fields

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The Journal of China Universities of Posts and Telecommunications 2015年第5期22卷 16-21页

作者： Liu Zhenhua zhang jie wen Qiaoyan Computer science department China Women's University School of Science Beijing University of Posts and Telecommunications State Key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications

Algebraic immunity is an important cryptographic property of Boolean functions. The notion of algebraic immunity of Boolean functions has been generalized in several ways to vector-valued functions over arbitrary finite fields. In this paper, the results of Ref. [25] are generalized to arbitrary finite fields. We obtain vector-valued functions over arbitrary finite fields such that their algebraic immunities can reach the upper bounds. Furthermore, all the component functions, together with their some nonzero linear combinations, of vector-valued Boolean functions achieved by this construction have optimal algebraic immunities simultaneously.

关键词： cryptography Boolean functions algebraic immunity

On Support τ-tilting Modules over Endomorphism Algebras of Rigid Ob jects

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Acta Mathematica Sinica,English Series 2015年第9期31卷 1508-1516页

作者： wen CHANG jie zhang Bin ZHU Department of Mathematical Sciences Tsinghua University School of Mathematics and Statistics Beijing institute of technology

We consider a Krull-Schmidt, Hom-finite, 2-Calabi Yau triangulated category with a basic rigid object T, and show a bijection between the set of isomorphism classes of basic rigid objects in the finite presented category pr T of T and the set of isomorphism classes of basic T-rigid pairs in the module category of the endomorphism algebra Endc（T）op. As a consequence, basic maximal objects in prT are one-to-one correspondence to basic support τ-tilting modules over Endc（T）op. This is a generalization of correspondences established by Adachi-Iyama-Reiten.

关键词： Rigid object maximal rigid object τ-rigid object finite presented category

On Ekeland's Variational Principle for Set-Valued Mappings

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Acta Mathematicae Applicatae Sinica 2007年第1期23卷 141-148页

作者： Sheng-jie Li wen-yan zhang College of Mathematics and Science Chongqing University Chongqing 400044 China

In this paper, we derive a general vector Ekeland variational principle for set-valued mappings, which has a dosed relation to εk^0 -efficient points of set-valued optimization problems. The main result presented in ... 详细信息

关键词： Vector Ekeland variational principle nonlinear scalarization function metric space set-valued mapping

高中英语教材内容教学转化的现实问题与实践进路

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教学与管理 2025年第1期 67-71页

作者：章策文江苏省南京市金陵中学南京210005

教材是静态的呈现和展示,教学是动态的实践和生成,而落实教材内容的教学转化是实施有效教学的前提和保障。在当前教材内容教学转化过程中,存在过度关注单一语篇研读而忽视教材逻辑结构的理解、过度关注话题引领忽视教材育人意涵的体悟... 详细信息

教材是静态的呈现和展示,教学是动态的实践和生成,而落实教材内容的教学转化是实施有效教学的前提和保障。在当前教材内容教学转化过程中,存在过度关注单一语篇研读而忽视教材逻辑结构的理解、过度关注话题引领忽视教材育人意涵的体悟、过度关注语言知识呈现忽视教材文化现象的剖析、过度关注板块教学设计忽视教材学习资源的统整、过度关注教学内容转化忽视教材学习评价的落实等现象。为此,教师在进行教材内容教学转化时要以专家的视角分析教材逻辑、以育人的视角探究主题意义、以共享的视角培养文化意识、以学生的视角整合学习资源、以补偿的视角指引自我评价。

关键词：教学转化教材逻辑教材理解高中英语

80岁以上患者急性梗阻性化脓性胆管炎合理治疗方式的选择

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世界华人消化杂志 2008年第26期16卷 3005-3008页

作者：王雪峰周学平李松岗张文杰顾钧李济宇上海交通大学医学院附属新华医院普外科上海市200092

目的:探讨内窥镜逆行胰胆管造影术(ERCP)治疗80岁以上患者急性梗阻性化脓性胆管炎的疗效、安全性及合理治疗方式的选择.方法:收集2001-01/2007-12我院80岁以上由结石引起的急性梗阻性化脓性胆管炎患者439例,根据不同处理方式分为内镜治... 详细信息

目的:探讨内窥镜逆行胰胆管造影术(ERCP)治疗80岁以上患者急性梗阻性化脓性胆管炎的疗效、安全性及合理治疗方式的选择.方法:收集2001-01/2007-12我院80岁以上由结石引起的急性梗阻性化脓性胆管炎患者439例,根据不同处理方式分为内镜治疗组(n=279)、手术治疗组(n=94)和保守治疗组(n=66),分析三组治疗方法的疗效、并发症发生率、死亡率、住院时间和住院费用等.结果:保守治疗组和手术治疗组病死率分别为16.7%和8.5%,内镜治疗组死亡2例,14例失访.内镜治疗组并发症发生率明显低于手术治疗组(3.9%vs34.0%,P<0.01),死亡率、住院时间和住院费(万元)明显低于手术治疗组和保守治疗组(0.72%vs8.5%,16.7%;7.3±2.8dvs11.4±3.7d,15.3±4.9d;1.23±0.54vs1.55±0.79,1.56±0.84,均P<0.05);手术治疗组的死亡率、住院时间也较保守治疗组低(均P<0.05).结论:内镜治疗80岁以上患者急性梗阻性化脓性胆管炎安全有效,是其首选的治疗方式.

关键词： 80岁以上患者急性梗阻性化脓性胆管炎内窥镜逆行胰胆管造影术

Carbothermal reduction process of the Fe-Cr-O system

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International Journal of Minerals,Metallurgy and Materials 2013年第10期20卷 931-940页

作者： Yan-ling zhang Yang Liu wen-jie Wei State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing

Understanding the reduction behaviors and characteristics of the end products of Fe-Cr-O systems is very important not only for maximizing the recovery of metals from stainless steel dust but also for the subsequent reuse in metallurgical process. The present work first predicted the possible products thermodynamically when FeCr204 was reduced by C. The reduction behaviors by graphite of three kinds of Fe-Cr-O systems, i.e., FeCr204, Fe203q-Cr203, and Feq-Cr203, were then investigated in 1350-1550℃. Further, the microstructures of final products and element distribution conditions were examined. The results suggest that, thermodynamically, the mass of products for the carbothermal reduction of FeCr204 is a strong function of temperature, and the initial carbon content is used. More Fe-Cr-C solution and less residual carbon content are obtained at higher temperatures and lower no：no ratios （the initial molar ratio of C to O in the sample）. Experimental data show that the sample amount tends to affect the reduction rate, and the residual carbon content strongly depends on nc：no. With regard to the phases present in products during the reaction process, metal carbides tend to form in the initial stage, whereas Fe-Cr-C solution forms when the degree of reduction is sufficiently high.

关键词： stainless steel dust ternary systems carbothermal reduction reaction kinetics