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青海湖地区紫花针茅型高寒草原群落特征变化

草地学报 2024年第4期32卷 1204-1209页

作者：王婷史倩倩祁得胜陈克龙杜岩功青海师范大学生命科学学院青海西宁810008 青海湖国家级自然保护区管理局青海海北812300 中国科学院西北高原生物研究所青海西宁810001

气候变暖促进青藏高原高寒草原分布面积逐渐增加,但有关紫花针茅(Stipa purpurea)型高寒草原生产力与物种丰富度长期变化特征及其驱动因素尚不明确。本研究连续13年观测青海湖地区高寒草地地上生物量、物种丰富度和盖度等指标,阐明了植... 详细信息

气候变暖促进青藏高原高寒草原分布面积逐渐增加,但有关紫花针茅(Stipa purpurea)型高寒草原生产力与物种丰富度长期变化特征及其驱动因素尚不明确。本研究连续13年观测青海湖地区高寒草地地上生物量、物种丰富度和盖度等指标,阐明了植被群落特征的长期变化规律,采用结构方程模型,解析了紫花针茅型高寒草原生产力和物种丰富度的主要影响因素。结果表明,高寒草原地上生物量和物种丰富度均呈现较强的波动上升趋势,平均鲜重和物种数分别为215.41 g·m^(-2)和15,高物种丰富度促进生产力增加;高寒草原群落总盖度和平均高度呈现显著增加趋势。紫花针茅型高寒草原地上生物量和总盖度分别受到年均气温和生产力的显著影响。未来增温气候情景将会显著增加青海湖地区紫花针茅型高寒草原生物量,但降雨量增加会降低物种丰富度。

关键词：高寒草原地上生物量物种丰富度年均气温

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白云石/三聚氰胺复合材料制备及吸附结晶紫性能研究

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化学研究与应用 2024年第8期36卷 1718-1724页

作者：玉澜时倩倩文胜陈燕萌兰兴先蒋才云广西科技师范学院广西来宾546199

以白云石和三聚氰胺为原料,热聚合制备白云石/三聚氰胺复合吸附材料,以结晶紫的吸附率为评介指标探讨复合材料对结晶紫的最佳吸附条件。结果显示复合材料对结晶紫最佳吸附条件是:复合材料投加量为0.75 g、结晶紫溶液初始浓度300 mg/L、... 详细信息

以白云石和三聚氰胺为原料,热聚合制备白云石/三聚氰胺复合吸附材料,以结晶紫的吸附率为评介指标探讨复合材料对结晶紫的最佳吸附条件。结果显示复合材料对结晶紫最佳吸附条件是:复合材料投加量为0.75 g、结晶紫溶液初始浓度300 mg/L、反应时间100 min,对结晶紫吸附率达97.3%。动力学拟合发现吸附反应符合准二级动力学方程和Langmuir等温方程模型,即吸附材料对结晶紫的吸附过程以单分子层的化学吸附为主。

关键词：白云石复合材料吸附结晶紫

PN/A工艺快速实现老龄垃圾渗滤液脱氮中试研究

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中国给水排水 2024年第13期40卷 68-72页

作者：张献旭奚士锋桂林涛史茜茜陈振国范俊豪汪晓军武汉环投固废运营有限公司湖北武汉430000 华南师范大学环境学院广东广州510006 华南理工大学环境与能源学院广东广州510006

以某垃圾填埋场老龄垃圾渗滤液为处理对象,构建了一套前置亚硝化反硝化-部分亚硝化(PN)/厌氧氨氧化(A)工艺的中试系统,探究其对该老龄垃圾渗滤液低碳脱氮处理的快速启动与适用性。结果表明,在已有培养成熟的厌氧氨氧化菌种基础上,该中... 详细信息

以某垃圾填埋场老龄垃圾渗滤液为处理对象,构建了一套前置亚硝化反硝化-部分亚硝化(PN)/厌氧氨氧化(A)工艺的中试系统,探究其对该老龄垃圾渗滤液低碳脱氮处理的快速启动与适用性。结果表明,在已有培养成熟的厌氧氨氧化菌种基础上,该中试系统仅用23 d就达到了15 kg/d的氨氮去除量;通过前置反硝化去除渗滤液中的大部分可生化有机物后,系统对老龄垃圾渗滤液中氨氮、总氮和COD的平均去除率分别可达到95.1%、94.3%、67.9%;经济核算结果表明,该工艺的处理成本(以去除NH_(4)^(+)-N计)仅为9.3元/kg,远低于硝化-反硝化工艺。

关键词：老龄垃圾渗滤液亚硝化反硝化厌氧氨氧化快速启动

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基质pH对欧洲报春开花品质的影响

林业科学研究 2024年第4期37卷 85-94页

作者：陈华乐温静怡唐天琪杨佳维高星赵婷婷苏齐珍史倩倩西北农林科技大学风景园林艺术学院陕西杨凌712100 秦岭国家植物园陕西西安710000

[目的]探究不同梯度基质pH(4.5、5.5、6.5、7.5)对欧洲报春开花品质的影响,为欧洲报春精细化栽培提供一定的理论基础。[方法]选取了4个不同花色的欧洲报春品种(‘靓丽风景’、‘火热情人’、‘蓝色安吉星’、‘黄丽’),采用硫酸亚铁和... 详细信息

[目的]探究不同梯度基质pH(4.5、5.5、6.5、7.5)对欧洲报春开花品质的影响,为欧洲报春精细化栽培提供一定的理论基础。[方法]选取了4个不同花色的欧洲报春品种(‘靓丽风景’、‘火热情人’、‘蓝色安吉星’、‘黄丽’),采用硫酸亚铁和氢氧化钠溶液将盆栽基质酸碱度调节为不同梯度,观察株高、花叶生长量等形态指标,并测定细胞保护酶活性、花色素含量、质膜透性等数据,研究基质pH对欧洲报春开花品质的影响。[结果]欧洲报春在基质pH5.5和pH6.5条件下花朵形态较好,在其他pH条件下生长均受到抑制。花瓣的L*值随酸碱胁迫下降,花青苷和类黄酮含量随基质pH值的增加呈下降趋势,而‘火热情人’花瓣细胞液pH值有小幅度上升。与CK相比,4个品种的CAT活性均在pH4.5处理下极显著或显著上升。形态指标与生理指标相关性分析表明POD与类胡萝卜素含量相关性最高,而与花青苷含量相关性最低。主成分分析和隶属函数综合评价结果表明花瓣细胞液pH、叶片相对含水量、开花数、CAT活性、可溶性糖含量、株高可作为评价欧洲报春在不同基质pH下开花品质的主要指标,其中无论在任何基质pH条件下‘蓝色安吉星’开花品质均最好。[结论]欧洲报春开花品质最佳的栽培基质pH为5.5~6.5,在不同基质pH胁迫下4个品种开花品质由高到低依次为:‘蓝色安吉星’、‘靓丽风景’、‘火热情人’、‘黄丽’。

关键词：欧洲报春基质pH 开花品质花色生理

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基于一个四维超混沌系统的图像加密算法

计算机仿真 2024年第4期41卷 237-244,259页

作者：王越安新磊施倩倩刘思洋兰州交通大学数理学院甘肃兰州730070

针对低维混沌系统复杂性低、应用在图像加密中效果差等问题,通过相图、分岔图、Lyapunov指数谱以及谱熵复杂度等方面探究了一个四维超混沌系统的动力学特性及其加密应用。仿真结果表明上述系统的混沌状态分布在较大的参数范围内并且具... 详细信息

针对低维混沌系统复杂性低、应用在图像加密中效果差等问题,通过相图、分岔图、Lyapunov指数谱以及谱熵复杂度等方面探究了一个四维超混沌系统的动力学特性及其加密应用。仿真结果表明上述系统的混沌状态分布在较大的参数范围内并且具有较大的复杂度值,说明上述系统能够很好的应用于图像加密。为此设计了一种基于四维超混沌的图像加密方案。算法主要利用改进的Arnold变换将明文图像的像素点位置进行扰乱,并通过加取模运算对置乱后的图像进行扩散,得到加密图像。最后通过密钥空间、相邻像素间相关性、信息熵、直方图以及差分攻击等方面分析了算法的安全性能。实验结果表明,上述加密算法不仅能够有效地对图像进行加密而且具有较高的安全性能。

关键词：超混沌系统置乱扩散图像加密

Rediscovery and analysis of Phytophthora carbohydrate esterase(CE) genes revealing their evolutionary diversity

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Journal of Integrative Agriculture 2018年第4期17卷 878-891页

作者： qian Kun LI Deng-hui LIN Run-mao shi qian-qian MAO Zhen-chuan YANG Yu-hong FENG Dong-xin XIE Bing-yan Institute of Vegetables and Flowers Chinese Academy of Agricultural Sciences College of Life Sciences Beijing Normal University Key Laboratory of Biology and Genetic Improvement of Horticultural Crops Ministry of Agriculture

A continuous co-evolutionary arms-race between pathogens and their host plants promotes the development of pathogenic factors by microbes, including carbohydrate esterase(CE) genes to overcome the barriers in plant cell walls. Identification of CEs is essential to facilitate their functional and evolutionary investigations; however, current methods may have a limit in detecting some conserved domains, and ignore evolutionary relationships of CEs, as well as do not distinguish CEs from proteases. Here, candidate CEs were annotated using conserved functional domains, and orthologous gene detection and phylogenetic relationships were used to identify new CEs in 16 oomycete genomes, excluding genes with protease domains. In our method, 41 new putative CEs were discovered comparing to current methods, including three CE4, 14 CE5, eight CE12, five CE13, and 11 CE14. We found that significantly more CEs were identified in Phytophthora than in Hyaloperonospora and Pythium, especially CE8, CE12, and CE13 that are putatively involved in pectin degradation. The abundance of these CEs in Phytophthora may be due to a high frequency of multiple-copy genes, supporting by the phylogenetic distribution of CE13 genes, which showed five units of Phytophthora CE13 gene clusters each displaying a species tree like topology, but without any gene from Hyaloperonospora or Pythium species. Additionally, diverse proteins associated with products of CE13 genes were identified in Phytophthora strains. Our analyses provide a highly effective method for CE discovery, complementing current methods, and have the potential to advance our understanding of function and evolution of CEs.

关键词： Phytophthora carbohydrate esterase gene prediction comparative genomic analysis evolution diversity

The tangential k-Cauchy-Fueter type operator and Penrose type integral formula on the generalized complex Heisenberg group

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Applied Mathematics(A Journal of Chinese Universities) 2024年第1期39卷 181-190页

作者： REN Guang-zhen shi Yun KANG qian-qian Department of Mathematics Zhejiang International Studies UniversityHangzhou 310023China Department of Mathematics Zhejiang University of Science and TechnologyHangzhou 310023China

The tangential k-Cauchy-Fueter operator and k-CF functions are counterparts of the tangential Cauchy–Riemann operator and CR functions on the Heisenberg group in the theory of several complex variables,*** this paper,we introduce a Lie group that the Heisenberg group can be imbedded into and call it generalized complex *** investigate quaternionic analysis on the generalized complex *** also give the Penrose integral formula for k-CF functions and construct the tangential k-Cauchy-Fueter complex.

关键词： the generalized complex Heisenberg group the tangential k-Cauchy-Fueter type operator Penrose-type integral formula

Biomimetic chitin hydrogel via chemical transformation

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Nano Research 2024年第2期17卷 771-777页

作者： Rui-Rui Liu qian-qian shi Yu-Feng Meng Yong Zhou Li-Bo Mao Shu-Hong Yu Division of Nanomaterials&Chemistry Hefei National Research Center for Physical Sciences at the MicroscaleDepartment of ChemistryInstitute of Biomimetic Materials&ChemistryAnhui Engineering Laboratory of Biomimetic MaterialsUniversity of Science and Technology of ChinaHefei 230026China College&Hospital of Stomatology Key Laboratory of Oral Diseases Research of Anhui ProvinceAnhui Medical UniversityHefei 230032China Department of Dental Implantology College&Hospital of StomatologyAnhui Medical UniversityHefei 230032China

Chitin hydrogel has been recognized as a promising material for various biomedical applications because of its biocompatibility and ***,the fabrication of strong chitin hydrogel remains a big challenge because of the insolubility of chitin in many solvents and the reduced chain length of chitin regenerated from *** herein introduce the fabrication of chitin hydrogel with biomimetic structure through the chemical transformation of chitosan,which is a water-soluble deacetylated derivative of *** reacetylation of the amino group in chitosan endows the obtained chitin hydrogel with outstanding resistance to swelling,degradation,extreme temperature and pH conditions,and organic *** chitin hydrogel has excellent mechanical properties while retaining a high water content(more than 95 wt.%).It also shows excellent antifouling performance that it resists the adhesion of proteins,bacteria,blood,and ***,as the initial chitosan solution can be feasibly frozen and templated by ice crystals,the chitin hydrogel structure can be either nacre-like or wood-like depending on the freezing method of the precursory chitosan *** to these anisotropic structures,such chitin hydrogel can exhibit anisotropic mechanics and mass transfer *** current work provides a rational strategy to fabricate chitin hydrogels and paves the way for its practical applications as a superior biomedical material.

关键词： chitin hydrogel biomimetic structure chemical stability mechanical strength antifouling

A study of the flat-band potential of n-type InP semiconductor electrode

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Acta Chimica Sinica(English Edition) 1983年第1期1卷 2-10页

作者： qian shi-yuan qian Dao-sun SUN Bi-rou Department of Applied Chemistry Shanghai Jiao Tong University Department of Applied Chemistry Shanghai Jiao Tong University

The flat-band potentials of n-type InP in different electrolytes were determined by open-circuit photopotential and differential capacitance *** influences of such factors asredox couples,pH value of the solutions,AC frequency,crystalline face and surface treatment ofthe InP electrode were *** parameters of the electrode were also calculated therefrom.

关键词： InP A study of the flat-band potential of n-type InP semiconductor electrode type