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超临界循环流化床锅炉深度调峰时水冷壁流动不稳定特性计算分析

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西安交通大学学报 2025年第1期59卷 68-77,92页

作者：李维腾郭泽瑞韩磊杨冬西安交通大学动力工程多相流国家重点实验室西安710049

针对深度调峰时超临界循环流化床锅炉水冷壁管道内的汽液两相流动不稳定问题,提出了一种适用于不同工况的频域法数学模型。通过对质量、能量、动量方程进行小扰动线性化后经拉普拉斯变换得到了用于描述管道内汽液流体流动稳定性的传递函... 详细信息

针对深度调峰时超临界循环流化床锅炉水冷壁管道内的汽液两相流动不稳定问题,提出了一种适用于不同工况的频域法数学模型。通过对质量、能量、动量方程进行小扰动线性化后经拉普拉斯变换得到了用于描述管道内汽液流体流动稳定性的传递函数,通过图解奈奎斯特图的方法判断管内工质流动的稳定性。然后,通过该模型计算了某350 MW超临界循环流化床锅炉水冷壁管段的不稳定边界并研究了不同参数对流动不稳定特性的影响。计算结果表明:所选回路在20%和50%锅炉最大连续蒸发量负荷发生流动不稳定时,热负荷分别为76.09 kW·m^(-2)和113.52 kW·m^(-2),水冷壁管道流动稳定且安全;入口过冷度对临界热流密度的影响呈非单值性;增大质量流速使流体的进口和出口密度差减小,有利于流动的稳定;增大入口节流系数,可以抑制入口处流量的脉动,有利于流动的稳定;在不同的工况条件下,改变管段倾斜角度会对流动稳定性产生不同的影响。

关键词：深度调峰流动不稳定性频域法超临界循环流化床锅炉

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Clinicopathological differences between patients with schistosomal appendicitis and non schistosomal appendicitis:A retrospectively study of past ten years

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World Journal of Clinical Cases 2025年第2期13卷 24-32页

作者： Xiao-Yi Wang Yao Hao Zi-Jian Wang xiu-liang Xu Jiang-Hua Yang Department of Infectious Diseases The First Affiliated of Wannan Medical CollegeWuhu 241001Anhui ProvinceChina

BACKGROUND Chronic schistosomiasis causes multiple organ and multiple system diseases,especially the digestive *** eggs are mainly deposited in the stomach,liver and colorectal,but a few eggs are deposited in the appendix and cause *** present,there are few studies on schistosomal *** To explore the differences in epidemiological,clinical and pathological characteristics between schistosomal appendicitis and non-schistosomal appendicitis over the past decade in order to assess the impact of schistosomiasis on *** The differences of general data,clinical data and laboratory examination data of patients with appendicitis from October 2013 to October 2023 were retrospectively *** patients were divided into two groups for *** were 136 patients in schistosomal appendicitis group and 5418 patients in non-schistosomal appendicitis *** Schistosomal appendicitis accounted for 2.45%of all patients with appendicitis,and the annual proportion in the past decade was 2.2%,2.9%,1.8%,1.9%,3.4%,3.1%,1.9%,1.6%,3%,2.6%,*** prevalence of schistosomal appendicitis was middle-aged and elderly males,with an average age of 61.73±15.335 *** main population of non-schistosomal appendicitis was middle-aged men,with an average age of 35.8±24.013 years(Plicated with colorectal cancer was higher than that of nonschistosomal appendicitis patients(OR=5.087;95%CI:1.427-

关键词： Schistosomal appendicitis Schistosomiasis Appendix Colorectal cancer Clinicopathological characteristics

Correlation between the rock mass properties and maximum horizontal stress:A case study of overcoring stress measurements

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 39-48页

作者： Peng li Meifeng Cai Shengjun Miao Yuan li Yu Wang Key Laboratory of Ministry of Education for Efficient Mining and Safety of Metal Mines University of Science and Technology BeijingBeijing 100083China State Key Laboratory of Coal Resources and Safe Mining China University of Mining and TechnologyXuzhou 221116China

Understanding the mechanical properties of the lithologies is crucial to accurately determine the horizontal stress *** investigate the correlation between the rock mass properties and maximum horizontal stress,the three-dimensional(3D)stress tensors at 89 measuring points determined using an improved overcoring technique in nine mines in China were adopted,a newly defined characteristic parameter C_(ERP)was proposed as an indicator for evaluating the structural properties of rock masses,and a fuzzy relation matrix was established using the information distribution *** results indicate that both the vertical stress and horizontal stress exhibit a good linear growth relationship with *** is no remarkable correlation between the elastic modulus,Poisson's ratio and depth,and the distribution of data points is scattered and ***,there is no obvious relationship between the rock quality designation(RQD)and *** maximum horizontal stress σ_(H) is a function of rock properties,showing a certain linear relationship with the C_(ERP)at the same *** addition,the overall change trend of σ_(H) determined by the established fuzzy identification method is to increase with the increase of C_(ERP).The fuzzy identification method also demonstrates a relatively detailed local relationship betweenσ_H and C_(ERP),and the predicted curve rises in a fluctuating way,which is in accord well with the measured stress data.

关键词： overcoring stress measurements elastic modulus Poisson's ratio rock quality designation maximum horizontal stress fuzzy identification

Some questions about landscape modelling

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Journal of Environmental Sciences 2001年第4期13卷 459-465页

作者： Michel Godron li xiu-zhen CCAS F18410BrinonFrance Institute of Applied Ecology Chinese Academy of SciencesShenyang 110016China

The paper discusses mainly about the modelling process and related problems with examples from Chinese and French cases. Five practical problems must be solved for modelling the functioning of any landscape: ( 1) The field data are necessarily taken with a sampling procedure that implies a spatial (and often temporal) scale. (2) Every landscape modelled has to be identified, delimited and characterised before application of the hierarchical theory. (3) The functioning of a landscape involves data of multiple types (climate, soil, vegetation, fauna, buildings, communications, economy, aesthetics, etc.) which must be integrated in a holistic approach. (4) Every landscape is spatially heterogeneous, and the structure of the model must be more or less isomorphic with its heterogeneity. ( 5) The evolution of the landscape must be modelled on a rather long period of time. For all these reasons, it is necessary to build ad hoc models. Object-oriented computing languages may be useful for this purpose.

关键词： landscape modelling scale hierarchy holistic approach application

Interfacial Zn2+-solvation regulator towards reversible and stable Zn anode

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Journal of Energy Chemistry 2025年第1期100卷 684-692页

作者： Miao Zhou Xiongbin Luo Hang li Shan Guo Zhuang Tong Xiaotao Zhou Xu li Zhaohui Hou Shuquan liang Guozhao Fang College of Mechanical Engineering Key Laboratory of Hunan Province for Advanced Carbon-based Functional Materials Hunan Institute of Science and Technology School of Materials Science and Engineering Key Laboratory of Electronic Packaging and Advanced Functional Materials of Hunan Province Central South University College of Materials and Metallurgy Guizhou University National Energy Metal Resources and New Materials Key Laboratory Central South University

Aqueous zinc-ion batteries （AZIBs） are fundamentally challenged by the instability of the electrode/electrolyte interface,predominantly due to irreversible zinc （Zn） deposition and hydrogen ***,the intricate mechanisms behind the electrochemical discrepancies induced by interfacial Zn2+-solvation and deposition behavior demand comprehensive *** molecules endowed with special functional groups （such as hydroxyl,carboxyl,etc.） have the potential to significantly optimize the solvation structure of Zn2+and regulate the interfacial electric double layer （EDL）.By increasing nucleation overpotential and decreasing interfacial free energy,these functional groups facilitate a lower critical nucleation radius,thereby forming an asymptotic nucleation model to promote uniform Zn ***,this study presents a pioneering approach by introducing trace amounts of n-butanol as solvation regulators to engineer the homogenized Zn （H-Zn） anode with a uniform and dense *** interfacial reaction and structure evolution are explored by in/ex-situ experimental techniques,indicating that the H-Zn anode exhibits dendrite-free growth,no by-products,and weak hydrogen evolution,in sharp contrast to the bare ***,the H-Zn anode achieves a remarkable Zn utilization rate of approximately 20% and simultaneously sustains a prolonged cycle life exceeding 500 ***,the H-Zn//NH4V4O10（NVO） full battery showcases exceptional cycle stability,retaining 95.04%capacity retention after 400 cycles at a large current density of 5 A *** study enlightens solvation-regulated additives to develop Zn anode with superior utilization efficiency and extended operational lifespan.

关键词： Aqueous zinc-ion batteries Interfacial reaction Asymptotic nucleation model Reversible and stable Zn anode

一株小菇属天麻萌发菌原生质体的制备、再生和应用

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陕西科技大学学报 2025年第1期43卷 58-66页

作者：李宏敬李锡琴粟忠祥仇全雷雷云霆西南林业大学林学院云南昆明650224 中国科学院昆明植物研究所云南昆明650201 昆明市林草局西山林场云南昆明650199 西藏波密高原藏天麻产业开发有限公司西藏林芝860318

小菇属真菌(Mycena spp.)遗传转化体系是研究其促进天麻种子萌发机制的重要基础,而其原生质体的制备和再生是该体系构建的必要条件.以小菇菌株MY004为实验材料,通过单因素分析和正交试验策略,探究其原生质体制备和再生的影响因素,构建... 详细信息

小菇属真菌(Mycena spp.)遗传转化体系是研究其促进天麻种子萌发机制的重要基础,而其原生质体的制备和再生是该体系构建的必要条件.以小菇菌株MY004为实验材料,通过单因素分析和正交试验策略,探究其原生质体制备和再生的影响因素,构建小菇原生质体制备和再生体系.结果表明,在含10 mM MES和0.7 M甘露醇的酶解缓冲液(pH=6)中,小菇MY004菌丝被10 mg/mL真菌溶壁酶在24℃条件下酶解3 h,其原生质体的释放率较高;经液体再生培养基(pH=5)培养3天,其原生质体再生效率可达2%.利用该体系,高效地完成了含报告基因eGFP转基因小菇的菌株纯化.小菇原生质体制备和再生体系可用于小菇遗传转化体系的快速构建,也将为小菇与天麻互作分子机制的研究提供基础平台.

关键词：小菇原生质体制备原生质体再生转基因菌株纯化

Elimination of ceftiofur hydrochloride residue in postpartum cows' milk after intramammary infusing at dry-off

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Journal of Integrative Agriculture 2018年第6期17卷 1234-1240页

作者： KANG Ji-jun liU Yi-ming ZHAO lei-lei XU Fei CHEN Xiao-jie YAN Xing li xiu-bo Feed Research Institute Chinese Academy of Agricultural Sciences

The purpose of this study was to investigate the residue elimination of ceftiofur hydrochloride in milk of postpartum cows after intramammary infusing at dry-off. An ultra-high performance liquid chromatography-tandem mass spectrometry （UPLC-MS/ MS） method was developed and validated to detect ceftiofur hydrochloride residue in milk. Through preprocessing, ceftiofur hydrochloride was derivatized into a more stable compound dedfuroyl ceftiofur acetamide （DCA） for further analysis. The linear range of DCA was 0.1 to 50 μg kg-1. Average recoveries of DCA were 82.52-105.86％. The intra-day and interday coefficients of variation （CV） were 2.95-9.82 and 6.41-7.43％, respectively. The limit of detection （LOD） and limit of quantitation （LOQ） scores were 0.05 and 0.1 μg kg-1, respectively. These parameters showed this method was reliable and valid. Twelve cows were administrated 10 mL ceftiofur hydrochloride by intramammary infusion （corresponding to 500 mg ceftiofur） to each udder after the last milking before the dry-off period. Milk was collected from each udder of cow at 12, 24, 36, 48, 60 and 72 h after calving and was mixed for each time point and each cow, then subjected to UPLC-MS/MS analysis. The results showed, the DCA concentrations in all milk samples were less than LOQ and the maximum residue limit （MRL） 100 μg kg-1, which suggested the withdrawal time of ceftiofur hydrochloride intramammary infusion used for preventing and curing mastitis in dry cows was 0 day. The study provided guidance for the clinical applications of ceftiofur hydrochloride intramammary infusion （dry cow）.

关键词： ceftiofur hydrochloride intramammary infusing dry cows milk residue

Preliminary prediction of the control reproduction number of COVID-19 in Shaanxi Province,China

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Applied Mathematics(A Journal of Chinese Universities) 2021年第2期36卷 287-303页

作者： li Zhi-min ZHANG Tai-lei GAO Jian-zhong li xiu-qing MA ling juan BAO Xiong-xiong School of Science Chang'an UniversityXi'an 710064China School of Ecological Environment Northwestern Polytechnical UniversityXi'an 710072China College of Economics and Management Shanxi Normal UniversityLinfen 041004China

Objectives Firstly,according to the characteristics of COVID-19 epidemic and the control measures of the government of Shaanxi Province,a general population epidemic model is ***,the control reproduction number of general population epidemic model is *** on the epidemic model of general population,the epidemic model of general population and college population is further established,and the control reproduction number is also *** For the established epidemic model,firstly,the expression of the control reproduc-tion number is obtained by using the next generation ***,the real-time reported data of COVID-19 in Shaanxi Province is used to fit the epidemic model,and the parameters in the model are estimated by least square method and ***,the Latin hypercube sampling method and partial rank correlation coefficient(PRCC)are adopted to analyze the sensitivity of the *** The control reproduction number remained at 3 from January 23 to January 31,then gradually decreased from 3 to slightly greater than 0.2 by using the real-time reports on the number of COVID-19 infected cases from Health Committee of Shaanxi Province in *** order to further control the spread of the epidemic,the following measures can be taken:(i)reducing infection by wearing masks,paying attention to personal hygiene and limiting travel;(i)improving isolation of suspected patients and treatment of symptomatic *** particular,the epidemic model of the collge population and the general population is estab-lished,and the control reproduction number is given,which will provide theoretical basis for the prevention and control of the epidemic in the colleges.

关键词： COVID-19 control reproduction number general population college population Shaanxi Province

Manufacture the conducting polymer with light

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Science China Chemistry 2025年第01期 8-9页

作者： Yang li Tianyu li Yan Ji Baoguang liu College of Electronic and Optical Engineering & College of Flexible Electronics (Future Technology) Nanjing University of Posts & Telecommunications

Poly(3,4-ethylenedioxythiophene) (PEDOT), heralded as the “king” of conducting polymers, is esteemed in bioelectronics for its mixed electronic and ionic conductivity, mechanical properties compatible with biological tissues, tunable healing ability and stability in diverse environments [1]. Based on additive manufacturing of three-dimensional structures,PEDOT realizes the implementation in the efficient production of flexible bioelectronics, the construction of intricate electrode-neural implantations, and the development of smart brain-computer-interfaces [2].

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