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气团来源和云雾过程对华南高山背景区亚微米气溶胶数谱分布的影响

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中国环境科学 2024年第1期44卷 28-36页

作者：周淑婷龚道程张诗炀张庆祖王文路刘小婷张涛周炎王伯光陈多宏王好暨南大学环境与气候研究院广东广州511443 南岭森林大气环境与碳中和野外科学观测研究站广东广州511443 台湾“中央研究院”环境变迁研究中心中国台湾台北11529 暨南大学附属第一医院眼科广东广州510630 广东省生态环境监测中心国家环境保护区域空气质量监测重点实验室广东广州510308

在南岭国家大气背景站(南岭站,海拔1690m)采用扫描电迁移率粒径谱仪(SMPS)对亚微米气溶胶的数浓度及粒径谱分布进行了观测.结合同期常规污染和气象数据,分析了不同来源气团与气象条件下气溶胶数谱分布的特征,探讨了典型云雾天气条件下... 详细信息

在南岭国家大气背景站(南岭站,海拔1690m)采用扫描电迁移率粒径谱仪(SMPS)对亚微米气溶胶的数浓度及粒径谱分布进行了观测.结合同期常规污染和气象数据,分析了不同来源气团与气象条件下气溶胶数谱分布的特征,探讨了典型云雾天气条件下气溶胶数浓度及谱分布的变化规律.研究结果表明:观测期间南岭站气溶胶的平均数浓度为1.14×10^(3)个/cm^(3),低于国内外大多数高山背景站,云雾天气多是造成南岭站气溶胶数浓度低的重要原因;气溶胶主要以爱根核模态和积聚模态为主,二者占总数浓度超过95%;气溶胶数浓度呈现下午高于上午的规律,峰值出现在下午14:00时左右.在途径珠三角的南部气团(占比66.2%)和途径湖南地区的北部气团(占比33.8%)影响下的气溶胶数谱分布均为双峰模态,但南部气团影响下的气溶胶数浓度约是北部气团(7.9×10^(2)个/cm^(3))影响下的2倍,且40~300nm粒径段的粒子数浓度明显升高.云雾时段的核模态和积聚模态气溶胶数浓度明显低于非云雾时段,总气溶胶数浓度下降幅度可达80%,说明云雾对气溶胶具有明显的清除作用;云雾发展过程中,气溶胶数浓度粒径分布变化规律呈现双峰型-单峰型-双峰型,谱宽不断收窄,且峰值粒径逐渐减小.

关键词：南岭国家背景站细颗粒物粒径谱气团传输雾

Pseudomonas simiae MHR6产胞外多糖条件优化及抗氧化活性

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草原与草坪 2024年第4期44卷 189-196页

作者：刘晓婷张琛韩江茹李晓林姚拓甘肃农业大学草业学院草业生态系统教育部重点实验室甘肃省草业工程实验室中‐美草地畜牧业可持续发展研究中心甘肃兰州730070 金昌市金川区农业技术推广服务中心甘肃金昌737100

【目的】研究培养条件对Pseudomonas simiae MHR6生长及胞外多糖(EPS)产量的影响,并探究其抗氧化活性,为新型农业生物制剂的开发利用提供可靠的理论依据。【方法】以EPS产量为指标,通过单因素试验对菌株MHR6产EPS条件进行优化,并对EPS... 详细信息

【目的】研究培养条件对Pseudomonas simiae MHR6生长及胞外多糖(EPS)产量的影响,并探究其抗氧化活性,为新型农业生物制剂的开发利用提供可靠的理论依据。【方法】以EPS产量为指标,通过单因素试验对菌株MHR6产EPS条件进行优化,并对EPS的羟基自由基(OH^(-))、超氧阴离子(O_(2)^(·-))和过氧化氢(H_(2)O_(2))的清除作用进行了研究。【结果】经优化后,MHR6产EPS的最佳培养条件是:培养时间5 d、温度28℃、初始pH值8、接种量3%。当EPS质量浓度为1.0 mg/mL时,其OH^(-)、O_(2)^(·-)和H_(2)O_(2)的清除率分别为56.94%、64.08%和31.69%。【结论】最佳培养条件下EPS产量达到最大值,为6.16 mg/mL,比优化前提高了24.9%。抗氧化实验结果表明MHR6所产的EPS具有良好的抗氧化活性。

关键词：胞外多糖培养条件优化自由基清除抗氧化活性

Directed Dynamic Small-World Network Model for Worm Epidemics in Mobile ad hoc Networks

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Chinese Physics Letters 2012年第1期29卷 49-52页

作者： ZHU Chen-Ping WANG Li liu xiao-ting YAN Zhi-Jun College of Science Nanjing University of Aeronautics and AstronauticsNanjing 210016 Kavli Institute for Theoretic Physics Beijing 100093 College of Science PLA University of Science and TechnologyNanjing 210016

We investigate the worm spreading process in mobile ad hoc networks with a susceptible-infected-recovered model on a two-dimensional plane.A medium access control mechanism operates within it,inhibiting transmission and relaying a message by using other nodes inside the node's transmitting circle during *** measure the rewiring probability p with the transmitting range r and the average relative velocity (v) of the moving nodes,and map the problem into a directed dynamic small-world network.A new scaling relation for the recovered portion of the nodes reveals the effect caused by geometric distance,which has been ignored by previous models.

关键词： Small scaling circle

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不同疏除处理对‘金太阳’杏果实品质的影响

北方果树 2024年第5期 24-25页

作者：薛玉莹刘晚冬马雯刘晓婷屈洋陕西省宝鸡市农业科学研究院陕西岐山722499 陕西省宝鸡市种子管理站陕西宝鸡721000

花果管理是果树管理的核心,‘金太阳’杏发育得好坏很大程度上取决于花果的管理。为了进一步研究不同疏除处理对杏果实品质的影响,作者以生产上主栽品种‘金太阳’杏为供试材料,通过疏蕾、疏花、疏果处理,研究杏的单果重、单核重、果实... 详细信息

花果管理是果树管理的核心,‘金太阳’杏发育得好坏很大程度上取决于花果的管理。为了进一步研究不同疏除处理对杏果实品质的影响,作者以生产上主栽品种‘金太阳’杏为供试材料,通过疏蕾、疏花、疏果处理,研究杏的单果重、单核重、果实可溶性固形物含量的变化。结果表明,疏蕾的效果最好,单果重、单核重和可溶性固形物含量最高。

关键词： ‘金太阳’杏疏蕾疏花疏果果实品质

An Inverse Method for Equivalent Gray Gas Radiation Characteristic Parameter

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Journal of Iron and Steel Research International 2013年第4期20卷 1-5页

作者： ZHANG Wei-jun YI Zhi liu xiao-ting LI Guo-jun CHEN Hai-geng College of Materials and Metallurgy Northeastern University

Compared with non-gray model,equivalent gray model has equal calculation accuracy but much higher computing *** solve the existing problems of the equivalent gray method,sole ternary model was *** the model,coupling solving process of energy balance equations is omitted and the model zone is real ***,the full furnace temperature and heat flow calculations are avoided,which makes it easier to find the relationship between the equivalent gray gas radiation characteristic parameter and the initial *** radiation characteristic parameter was calculated with different temperature combinations,different model zone sizes and different partial pressures of absorbent *** results show the similar variations in the absorption coefficient and emissivity for the equivalent gray model,which both decrease with the increase of the gas temperature and the surface temperature（especially the former one）as well as the model zone size while increase with the increase of the partial pressure of absorbent gas.

关键词： equivalent gray radiation characteristic parameter sole ternary model

Non-contact and full-field online monitoring of curing temperature during the in-situ heating process based on deep learning

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Advances in Manufacturing 2024年第1期12卷 167-176页

作者： Qiang-Qiang liu Shu-ting liu Ying-Guang Li Xu liu xiao-Zhong Hao College of Mechanical and Electrical Engineering Nanjing University of Aeronautics and AstronauticsNanjing210016People’s Republic of China School of Mechanical and Power Engineering Nanjing Tech UniversityNanjing211816People’s Republic of China

Online monitoring of the curing temperature field is essential to improving the quality and efficiency of the manufacturing process of composite *** embedded sensor-based technologies have difficulty monitoring the full temperature field or have to introduce heterogeneous items that could have an undesired impact on the *** this paper,a non-contact,full-field monitoring method based on deep learning that predicts the internal temperature field of composite parts in real time using surface temperature measurements of auxiliary materials is *** the proposed method,an average temperature monitoring accuracy of 97%is achieved in various heating *** addition,this method also demonstrates satisfying feasibility when a stronger thermal barrier covers the *** method was experimentally validated during the self-resistance electric heating process,in which the monitoring accuracy reached 93.1%.This method can potentially be applied to automated manufacturing and process control in the composites industry.

关键词： Online monitoring Curing temperature field Deep learning(DL) In-situ heating

Burning Numbers of Barbells

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Acta Mathematicae Applicatae Sinica 2024年第2期40卷 526-538页

作者： Hui-qing liu Rui-ting ZHANG xiao-lan HU Hubei Key Laboratory of Applied Mathematics&Faculty of Mathematics and Statistic Hubei UniversityWuhan 430062China Hubei Key Laboratory of Mathematical Sciences&School of Mathematics and Statistics Central China Normal UniversityWuhan 430079China

Motivated by a discrete-time process intended to measure the speed of the spread of contagion in a graph,the burning number b(G)of a graph G,is defined as the smallest integer k for which there are vertices x1,…xk su... 详细信息

关键词： burning number short/long barbell isometric subtree cycle

基于CRISPR-Cas12a核酸检测研究进展

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动物医学进展 2024年第8期45卷 94-98页

作者：刘晓婷李鹏左柯铭陈萌萌王亚新王凤雪温永俊内蒙古农业大学兽医学院农业农村部动物疾病临床诊疗技术重点实验室内蒙古呼和浩特010018

由病毒、细菌、真菌、寄生虫和其他病原微生物引起的疾病对人类健康构成极大威胁,如果能在疾病早期检测出来,就能够对传染性疾病起到关键的预防作用。近些年来,CRISPR-Cas系统在检测病原方面已被广泛应用,其中CRISPR-Cas12a弥补了Cas9... 详细信息

由病毒、细菌、真菌、寄生虫和其他病原微生物引起的疾病对人类健康构成极大威胁,如果能在疾病早期检测出来,就能够对传染性疾病起到关键的预防作用。近些年来,CRISPR-Cas系统在检测病原方面已被广泛应用,其中CRISPR-Cas12a弥补了Cas9的不能多点编辑的缺陷和Cas12a靶向DNA的特性,成为了热门的核酸检测工具。论文综述了Cas12a与Cas9的不同之处、Cas12a的发现、CRISPR-Cas12a的信号检测平台以及目前使用的检测方法。

关键词： CRISPR-Cas12a 核酸检测病毒

Construction of an immune-related gene signature for overall survival prediction and immune infiltration in gastric cancer

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World Journal of Gastrointestinal Oncology 2024年第3期16卷 919-932页

作者： xiao-ting Ma Xiu liu Kai Ou Lin Yang Department of Medical Oncology Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100021China

BACKGROUND Treatment options for patients with gastric cancer(GC)continue to improve,but the overall prognosis is *** use of PD-1 inhibitors has also brought benefits to patients with advanced GC and has gradually become the new standard treatment option at present,and there is an urgent need to identify valuable biomarkers to classify patients with different characteristics into *** To determined the effects of differentially expressed immune-related genes(DEIRGs)on the development,prognosis,tumor microenvironment(TME),and treatment response among GC patients with the expectation of providing new biomarkers for personalized treatment of GC *** Gene expression data and clinical pathologic information were downloaded from The Cancer Genome Atlas(TCGA),and immune-related genes(IRGs)were searched from *** were extracted from the intersection of the differentially-expressed genes(DEGs)and IRGs *** enrichment pathways of key genes were obtained by analyzing the Kyoto Encyclopedia of Genes and Genomes(KEGGs)and Gene Ontology(GO)*** identify genes associated with prognosis,a tumor risk score model based on DEIRGs was constructed using Least Absolute Shrinkage and Selection Operator and multivariate Cox *** tumor risk score was divided into high-and lowrisk *** entire cohort was randomly divided into a 2:1 training cohort and a test cohort for internal validation to assess the feasibility of the risk *** infiltration of immune cells was obtained using‘CIBERSORT,’and the infiltration of immune subgroups in high-and low-risk groups was *** GC immune score data were obtained and the difference in immune scores between the two groups was *** We collected 412 GC and 36 adjacent tissue samples,and identified 3627 DEGs and 1311 IRGs.A total of 482 DEIRGs were *** analysis showed that DEIRGs were mainly distributed in immunoglobulin complexes,receptor ligand activity,and s

关键词： Differentially expressed immune-related gene Immunotherapy Gastric cancer Risk score