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六岔河流域多水塘-沟渠系统中土壤养分空间变异特征研究

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水利学报 2011年第4期42卷 425-430页

作者：毛战坡王世岩周晓玲刘畅中国水利水电科学研究院水环境研究所北京100038 中国科学院生态环境研究中心北京100085

借助地理信息系统,利用地统计学中的半变量变异函数研究了巢湖北岸六岔河流域多水塘-沟渠系统中的土壤养分空间变异特征。研究结果表明:土壤中有机物(OM)、总氮(TN)、总磷(TP)、氨态氮(NH4-N)、硝态氮(NO3-N)的空间变异函数理论模型均... 详细信息

借助地理信息系统,利用地统计学中的半变量变异函数研究了巢湖北岸六岔河流域多水塘-沟渠系统中的土壤养分空间变异特征。研究结果表明:土壤中有机物(OM)、总氮(TN)、总磷(TP)、氨态氮(NH4-N)、硝态氮(NO3-N)的空间变异函数理论模型均符合球状模型,总磷、氨态氮、有机物空间异质性中的结构性变异大于随机变异;总氮、硝态氮的结构性变异小于随机变异。有机物、总氮、总磷、氨态氮、硝态氮等空间自相关范围具有明显的差异性,变化范围为123.9～517.36m,呈现出氨态氮>硝态氮>总氮>有机物>总磷,变化范围相差4倍左右,上述差异主要与养分特性、土地利用以及多水塘-沟渠系统景观等因素关系密切。

关键词：土壤养分多水塘-沟渠系统空间变异地统计学

带Leader的不确定高阶多智能体系统的L_2-L_∞一致

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控制理论与应用 2012年第9期29卷 1125-1131页

作者：莫立坡周艳杰周洪波北京工商大学理学院北京100048 南伊利诺伊大学计算机科学系

针对一类存在外部干扰,模型误差以及时滞的带Leader的高阶多智能体系统,利用L2-L∞方法研究了其一致性问题.首先给出了系统存在外部干扰和模型误差时的数学模型.然后针对有时滞和无时滞两种情况,利用Lyapunov函数的方法,分析了满足L2-L... 详细信息

针对一类存在外部干扰,模型误差以及时滞的带Leader的高阶多智能体系统,利用L2-L∞方法研究了其一致性问题.首先给出了系统存在外部干扰和模型误差时的数学模型.然后针对有时滞和无时滞两种情况,利用Lyapunov函数的方法,分析了满足L2-L∞性能指标下的一致问题,分别得到了相应闭环系统达到一致的条件.最后,仿真结果验证了所得结果的有效性.

关键词： L2-L∞一致高阶多智能体系统不确定性时滞

Promoting post-Traumatic Growth in Colorectal Cancer Patients:Exploring the Role of Social Support through a Chain Mediation Model

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Psycho-Oncologie 2024年第3期18卷 233-240页

作者： Xia Sun Qin Li yang Li Wenjun yan Shuai Gong Wenjing yan Department of General Surgery The Affiliated Hospital of Xuzhou Medical UniversityXuzhou221006China School of Nursing Xuzhou Medical UniversityXuzhou221004China School of Nursing Suzhou Medical College of Soochow UniversitySuzhou215006China

Colorectal cancer(CRC)poses signiﬁcant physical and psychological challenges that necessitate an exploration of factors inﬂuencing post-traumatic growth(PTG)for patient *** study aims to investigate the effects of positive psychological capital(PsyCap)and perceived stress on mediating the social support-PTG relation among 673 CRC *** support,positive PsyCap,perceived stress,and PTG were assessed through *** results indicated a direct prediction effect of social support on PTG(LICI=0.481,ULCI=0.644),with the direct effect being 59.5%.Both positive PsyCap and perceived stress exerted a mediating role in the correlation between social support and PTG,with the mediating effects occupying 29.4%(LICI=0.217,ULCI=0.343)and 5.7%(LICI=0.030,ULCI=0.082),*** PsyCap further had a chain mediating effect on perceived stress(LICI=0.031,ULCI=0.074),with the chain effect accounting for 5.4%.The total impact of social support on PTG was 100%(LICI=0.882,ULCI=1.008).This model underscores the pivotal role of social support in promoting PTG in CRC *** PsyCap serves as a crucial mediator in the social support-PTG link,with perceived stress playing a sequential mediating ***ﬁndings suggest that strengthening social support networks and cultivating positive PsyCap may reduce perceived stress and promote the development of PTG in CRC ***,intervention programs are recommended to improve the psychosocial well-being of CRC patients.

关键词： Social support positive psychological capital perceived stress mediating effect post-traumatic growth

Fatty acid hydratase for value-added biotransformation:A review

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Chinese Journal of Chemical Engineering 2020年第8期28卷 2051-2063页

作者： yan Zhang Bekir Engin Eser Peter Kristensen Zheng Guo Department of Engineering Faculty of Science and TechnologyAarhus UniversityGustav wieds vej 108000 AarhusDenmark Faculty of Engineering and Science Department of Chemistry and BioscienceAalborg University9220 AalborgDenmark

The synthesis of hydroxy fatty acids(HFAs) from renewable oil feedstock by addition of water onto C_C bonds has attracted great attention in recent years. Given that selective asymmetric hydration of non-activated C_C bonds has been proven difficult to achieve with chemical catalysts, enzymatic catalysis by fatty acid hydratases(FAHs) presents an attractive alternative approach to produce value-added HFAs with high regio-, enantioand stereospecificity, as well as excellent atom economy. Even though FAHs have just been investigated as a potential biocatalyst for a decade, remarkable information about FAHs in different aspects is available;however, a comprehensive review has not been archived. Herein, we summarize the research progresses on biochemical characterization, structural and mechanistic determination, enzyme engineering, as well as biotechnological application of FAHs. The current challenges and opportunities for an efficient utilization of FAHs in organic synthesis and industrial applications are critically discussed.

关键词： Hydroxy fatty acids Fatty acid hydratases Enzyme characterization Catalytic mechanism Enzyme engineering Biotransformation

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基于无线专网的配变实时监测管理系统

电力系统保护与控制 2009年第16期37卷 96-98页

作者：郑琰焦坡张晶莹郑州供电公司河南郑州450000 许继电气股份有限公司河南许昌461000

为了解决配电所远程实时监测中遇到的问题,进一步提高供电质量,设计了一种基于无线专网的实时监测管理系统,系统包括三大部分,分别是数据采集终端DTU、GPRS和GSM信道、监测中心,其中通信通道采用先进的APN技术建立无线专网进行通信,从... 详细信息

为了解决配电所远程实时监测中遇到的问题,进一步提高供电质量,设计了一种基于无线专网的实时监测管理系统,系统包括三大部分,分别是数据采集终端DTU、GPRS和GSM信道、监测中心,其中通信通道采用先进的APN技术建立无线专网进行通信,从而保证了整个系统可靠,高效,安全的运行。经过数据通信测试验证了方案的可行性。

关键词： DTU APN 配变无线专网监测中心

Adenoviral 15-lipoxygenase-1 gene transfer inhibits hypoxia-induced proliferation of retinal microvascular endothelial cells in vitro

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International Journal of Ophthalmology(English edition) 2012年第5期5卷 562-569页

作者： Ying yan, Yi-Qiao Xing Department of Ophthalmology Renmin Hospital of Wuhan University Wuhan 430060 Hubei Province China Department of Ophthalmology Wuhan General Hospital of Guangzhou Military Command of Chinese PLA Wuhan 430070 Hubei Province China Department of Ophthalmology Xiangyang Center Hospital Xiangyang 441021 Hubei Province China

AIM: To investigate whether 15-Lipoxygenase-1 (15-LOX-1) plays an important role in the regulation of angiogenesis, inhibiting hypoxia-induced proliferation of retinal microvascular endothelial cells (RMVECs) and the underlying mechanism. METHODS: Primary RMVECs were isolated from the retinas of C57/BL63 mice and identified by an evaluation for FITC-marked CD31. The hypoxia models were established with the Bio-bag and evaluated with a blood-gas analyzer. Experiments were performed using RMVECs treated with and without transfer. Ad-15-LOX-1 or Ad-vector both under hypoxia and normoxia condition at 12, 24, 48, 72 hours. The efficacy of the gene transfer was assessed by immunofluorescence staining. Cells proliferation was evaluated by the CCK-8 method. RNA and protein expressions of 15-LOX-1, VEGF-A, VEGFR-2, eNOs and PPAR-r were analyzed by real-time reverse transcription polymerase chain reaction (RT-PCR) and Western blot. RESULTS: Routine evaluation for FITC-marked CD31 showed that cells were pure. The results of blood-gas analysis showed that when the cultures were exposed to hypoxia for more than 2 hours, the po2 was 4.5 to 5.4 Kpa. We verified RMVECs could be infected with Ad-LS-LOX-for Ad-vectorvia Fluorescence microscopy. CCK-8 analysis revealed that the proliferative capacities of RMVECs in hypoxic group were significantly higher at each time point than they were in normoxic group (P poxic condition, the proliferative capacities of RMVECs in 15-LOX-1 group were significantly inhibited (Ppoxia group compared with normoxia group (Ppoxia group compared with normoxia group (Ppoxic condition, the expressions of VEGF-A, VEGF-R2 and eNOs mRNA decreased significantly in 15-LOX-1 group compared with hypoxia group (P<0.01). However, 15-LOX

关键词： 15-Lipoxygenase-1 hypoxia retinal microvascular endothelial cells retinal neovascularization

Recycling of crustal materials and implications for lithospheric thinning: Evidence from Mesozoic volcanic rocks in the Hailar-Tamtsag Basin, NE China

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Geoscience Frontiers 2021年第5期12卷 149-165页

作者： Zheng Ji yan-Long Zhang Chuan-Biao Wan Wen-Chun Ge Hao yang Yu Dong yan Jing College of Earth Sciences Jilin UniversityChangchun 130061China Exploration and Development Research Institute Daqing Oilfield Limited CompanyDaqing 163712China

Late Mesozoic Nb-rich basaltic andesites and high-Mg adakitic volcanic rocks from the Hailar-Tamtsag Basin,northeast China,provide important insights into the recycling processes of crustal materials and their role in late Mesozoic lithospheric *** Late Jurassic Nb-rich basaltic andesites(154±4 Ma)are enriched in large-ion lithophile and light rare earth elements,slightly depleted in high-field-strength elements,and have high TiO_(2),P_(2)O_(5),and Nb contents,and(Nb/Th)PM and Nb/U ratios,which together with the relatively depleted Sr-Nd-Hf isotopic compositions indicate a derivation from a mantle wedge metasomatized by hydrous melts from subducted oceanic *** Early Cretaceous high-Mg adakitic volcanic rocks(129-117 Ma)are characterized by low Y and heavy rare earth element contents,and high Sr contents and Sr/Y ratios,similar to those of rocks derived from partial melting of an eclogitic *** also have high Rb/Sr,K_(2)O/Na_(2)O,and Mg#values,and high MgO,Cr,and Ni *** geochemical features suggest that the adakitic lavas were derived from partial melting of delaminated lower continental crust,followed by interaction of the resulting melts with mantle material during their *** data,along with available geological,paleomagnetic,and geophysical evidence,lead us to propose that recycling of Paleo-Pacific oceanic crustal materials into the upper mantle due to flat-slab subduction and rollback of the Paleo-Pacific Plate during the late Mesozoic likely provided the precondition for lithospheric thinning in northeast China,with consequent lithospheric delamination causing recycling of continental crustal materials and further lithospheric thinning.

关键词： Late Mesozoic Lithospheric thinning Hailar-Tamtsag Basin Paleo-Pacific Plate Volcanic rock

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环冷机上球团冷却过程的仿真与优化

钢铁研究学报 2015年第6期27卷 12-17页

作者：江倩宋彦坡彭小奇中南大学能源科学与工程学院湖南长沙410083 湖南第一师范学院信息科学与工程系湖南长沙410205

为了探索环冷机关键结构参数和操作参数对球团冷却效果及过程节能降耗的优化途径,运用双能量方程建立了某球团厂的环冷机球团料层内部气、固相非平衡传热模型,应用"未反应核模型"建立了料层内部的主要化学反应(磁铁矿氧化)的反应速率计... 详细信息

为了探索环冷机关键结构参数和操作参数对球团冷却效果及过程节能降耗的优化途径,运用双能量方程建立了某球团厂的环冷机球团料层内部气、固相非平衡传热模型,应用"未反应核模型"建立了料层内部的主要化学反应(磁铁矿氧化)的反应速率计算模型,基于Matlab平台实现了对不同操作条件下球团冷却过程的数值仿真。对多个设计工况的仿真结果表明:以球团产量、冷却效果不变为约束,当料层厚度达原厚度的2倍时,环冷机3段排气温度分别提高50、71、33℃,并可节约用风23.6%,即适当增加料层厚度有利于能量回收和节约用风。

关键词：球团环冷机节能降耗数值模拟优化

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导弹防御系统中红外光电识别技术分析

红外与激光工程 2009年第5期38卷 759-766页

作者：吴瑕周焰崔建杨龙坡空军雷达学院预警监视情报系湖北武汉430019

目标识别问题是弹道导弹防御系统中的核心难题之一,针对弹道导弹突防中威胁目标群飞行各阶段呈现出的不同红外特性,介绍了天基红外系统和拦截弹的最新研究进展及其红外目标识别技术手段。在温度测量、测辐射强度、红外成像等关键技术方... 详细信息

目标识别问题是弹道导弹防御系统中的核心难题之一,针对弹道导弹突防中威胁目标群飞行各阶段呈现出的不同红外特性,介绍了天基红外系统和拦截弹的最新研究进展及其红外目标识别技术手段。在温度测量、测辐射强度、红外成像等关键技术方面,系统地论述了其在反导系统弹道目标识别中所运用的红外光电子学方法与技术,并且就相应的反红外识别手段——红外隐身与红外诱饵,进行了探讨。最后对导弹防御系统中红外目标识别与反识别的研究动向进行了展望,提出了进行导弹防御系统目标识别研究的总体建议。

关键词：红外目标识别光电子学导弹防御系统天基红外预警卫星拦截弹