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双向视ICP-OES法同时测定褐煤中锗和一些主要成灰元素

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光谱学与光谱分析 2005年第9期25卷 1496-1499页

作者：邹本东敖登高娃尚洪山其鲁内蒙古大学化学化工学院内蒙古呼和浩特010021 北京大学化学与分子工程学院北京100871

描述了ICPOES(高频电感耦合等离子体光学发射光谱)同时测定褐煤中ge和一些主要成灰元素Fe,Al,Ca,Mg,K,Na,Ti的方法。所使用的仪器是一台安装有双向视等离子体炬管和一个同时检测器的ICP光谱仪,这种技术允许分别在侧视和端视方式下同时... 详细信息

描述了ICPOES(高频电感耦合等离子体光学发射光谱)同时测定褐煤中ge和一些主要成灰元素Fe,Al,Ca,Mg,K,Na,Ti的方法。所使用的仪器是一台安装有双向视等离子体炬管和一个同时检测器的ICP光谱仪,这种技术允许分别在侧视和端视方式下同时测定主成分和微量元素。作者选取了适宜的仪器工作条件、选择了无干扰的分析谱线和合理地扣除了光谱背景,样品灰化后用HNO3/HF/HClO4混合酸消解,测定结果与国标方法吻合。仪器的检出限为0.00039～0.10μg·mL-1,方法的精密度RSD为0.79%～2.84%,样品平均回收率为92.38%。建立的方法可简便、快速、准确地对褐煤中锗及其他多种元素同时进行测定。

关键词： ICP-OES 褐煤锗成灰元素

Possible South-Dipping Mesozoic Subduction at Southern Tethys Ocean-Constrained from global Tectonic Reconstructions and Seismic Tomography

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Journal of Earth Science 2023年第1期34卷 260-279页

作者： Peilong Yan Nan Zhang Huaiyu Yuan Liang qi Xiaoxu Liu The Key Laboratory of Orogenic Belts and Crustal Evolution School of Earth and Space SciencesPeking UniversityBeijing100871China Earth Dynamics Research group School of Earth and Planetary SciencesCurtin UniversityPerthWA6845Australia ARC Centre of Excellence for Core to Crust Fluid Systems Macquarie UniversitySydneyNSW2109Australia

The evolution of the Tethys Ocean involved several episodes of ocean opening(including the Paleo-Tethys and Neo-Tethys) along its southern margin as terranes rifting away from eastern gondwana. These oceans were terminated by well observed north-dipping subduction as the same terranes accreted to southern Eurasia. However, the presence of south-dipping subduction, though geologically proposed by numerous studies, have generally been omitted in the reconstruction of Tethyan evolution. Here, we synthesize the Mesozoic south-dipping subduction evolutions in the global reconstruction and focus on two potential events located along the northern edges of Southwest Borneo Block and the Woyla Arc. We next evaluate their slab volumes after thermal diffusion in the current mantle. Fast velocity anomalies in the mantle beneath the same region are then converted to cold anomalies and their volumes are further estimated and compared to the volumes evaluated from these two Mesozoic south-dipping subduction. We further identify seismic fast velocity anomalies likely relevant to slab remnants of south-dipping Tethyan subduction in the present-day mantle beneath the Indian ocean and West Australia, and link them to arc systems in plate reconstructions. In addition, one more tectonic scenario relevant to the north-dipping subduction in our study region is also examined. We speculate the relationship and evolution between such south-dipping subduction and north-dipping subduction in the south of Tethys Oceans. The attempt to reconstruct intermittent south-dipping subduction systems in southern Tethys region represents an effort on assessing rifting mechanisms in the opening of the Tethys Ocean and break-up of eastern gondwana.

关键词： Tethys south-dipping subduction reconstruction seismic prospecting

Fabrication of high-stability Ni-PSF@PAO40 microcapsules and their lubricating properties in polyamide 6

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Friction 2022年第12期10卷 1985-1999页

作者： Wenli ZHANg Xiaowen qi Xiao YANg Yu DONg Bingli FAN Lei LIANg School of Mechanical Engineering Yanshan UniversityQinhuangdao 066004China Key Laboratory of Self-Lubricating Spherical Plain Bearing technology of Hebei Province Yanshan UniversityQinhuangdao 066004China Aviation Key Laboratory of Science and Technology on generic Technology of Self-Lubricating Spherical Plain Bearing Yanshan UniversityQinhuangdao 066004China School of Civil and Mechanical Engineering Curtin UniversityPerthWA 6845Australia Shanghai Research Institute of Synthetic Resins Co. Ltd.Shanghai 201702China

Novel Ni-PSF@PAO40 microcapsules(NPPMS)with high stability were prepared by using a combined processing method of electroless nickel plating and solvent *** results indicate that Ni is completely assembled on the surfaces of PSF/PAO40 microcapsules with the encapsulation capacity of NPPMS achieved at 50%.Organic solvents immersion shows that NPPMS have an excellent chemical *** thermal stability tests reveal that the softening temperature of NPPMS is increased up to over 400℃ while it becomes lower than 200℃ for PSF/PAO40 ***,NPPMS were embedded into polyamide 6(PA6)to prepare PA6/NPPMS *** cross-sectional morphology shows that NPPMS are intact in PA6 *** microhardness of PA6 is effectively improved with the incorporation of *** compared with neat PA6,the coefficient of friction(COF)for PA6/NPPMS composites with 10%NPPMS could be reduced by 87.7%(from 0.49 to 0.06)and the wear rate could be decreased by 96.8%(from 1.29×10^(-5) to 4.15×10^(-7) mm^(3)/(N·m)).Further studies confirmed that increasing test loads and test temperatures was beneficial to improve the lubrication performance of NPPMS despite the opposite trend occurred when increasing the sliding *** has been demonstrated that synergistic effects between PAO40 and Ni layer play an important role in improving the tribological properties of ***,NPPMS significantly improve the ability of microcapsules to resist a harsh environment,which has important scientific significance for expanding the use of microcapsules more practically in self-lubricating composites.

关键词： microcapsules electroless nickel high temperature resistant polyamide 6(PA6) friction and wear

Nd_(28)Fe_(66)B_6/Fe_(50)Co_(50)双层纳米复合膜的结构和磁性

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物理学报 2005年第10期54卷 4889-4893页

作者：敖琪张瓦利张熠吴建生上海交通大学高温材料与高温测试教育部重点实验室上海200030

利用磁控溅射法制备了Nd28Fe66B6/Fe50Co50双层纳米复合磁性薄膜,研究了其结构和磁性.经873K退火处理15min后,利用x射线衍射仪测定薄膜晶体结构,采用俄歇电子能谱仪估算薄膜厚度和超导量子干涉仪测量其磁性.磁性测量表明,1)该系列薄膜... 详细信息

利用磁控溅射法制备了Nd28Fe66B6/Fe50Co50双层纳米复合磁性薄膜,研究了其结构和磁性.经873K退火处理15min后,利用x射线衍射仪测定薄膜晶体结构,采用俄歇电子能谱仪估算薄膜厚度和超导量子干涉仪测量其磁性.磁性测量表明,1)该系列薄膜具有垂直于膜面的磁各向异性.从起始磁化曲线和小回线的形状特征可知,矫顽力机制主要是由畴壁钉扎控制.2)对于固定厚度(10nm)层的硬磁相Nd-Fe-B和不同厚度(dFeCo=1—100nm)层软磁相FeCo双层纳米复合膜,剩磁随软磁相FeCo厚度的增加快速增加,而矫顽力则减少.当dFeCo=5nm时,最大磁能积达到160×103A/m.磁滞回线的单一硬磁相特征说明,硬磁相Nd-Fe-B层和软磁相FeCo层之间的相互作用使两相很好地耦合在一起.剩磁和磁能积的提高是由于两相磁性交换耦合所致.

关键词： Nd-Fe-B/FeCo双层纳米复合膜交换耦合磁性增强纳米复合膜磁性薄膜晶体结构 Nd-Fe-B 超导量子干涉仪俄歇电子能谱仪矫顽力机制

甘薯褪绿矮化病毒西非株系RT-RPA-LFD检测方法的建立与应用

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中国农业科学 2024年第14期57卷 2781-2790页

作者：王永江乔奇王爽赵付枚田雨婷张德胜张振臣河南省农业科学院植物保护研究所/河南省农作物病虫害防治重点实验室/农业农村部华北南部作物有害生物综合治理重点实验室

【目的】利用逆转录酶重组酶聚合酶扩增（reverse transcriptase recombinase polymerase amplification,RT-RPA）结合侧向流层析（lateral flow dipstick,LFD）试纸条技术，建立甘薯褪绿矮化病毒（sweet potato chlorotic stunt virus,SPCSV）西非株系（west African strain,wa）的RT-RPA-LFD检测方法。【方法】根据SPCSV-wa外壳蛋白基因和热激蛋白基因的保守序列设计并筛选扩增效果好、特异性强的引物和探针。然后对引物和探针的浓度、扩增体系、温度、反应时间等条件进行优化，建立SPCSV-wa的RT-RPA-LFD检测方法。利用该方法对SPCSV-EA、甘薯羽状斑驳病毒（sweet potato feathery mottle virus,SPFMV）、甘薯潜隐病毒（sweet potato latent virus,SPLV）、甘薯g病毒（sweet potato virus g,SPVg）等常见的甘薯病毒进行检测，验证方法的特异性；将感染SPCSV-wa甘薯叶片样品总RNA进行10倍梯度稀释，分别采用RT-PCR和RT-RPA-LFD进行检测，比较RT-PCR和RT-RPA-LFD方法的灵敏度；对采自田间的甘薯样品和试管苗样品进行RT-RPA、RT-RPA-LFD和RT-PCR检测，验证该方法的实用性。【结果】建立了SPCSV-wa的RT-RPA-LFD检测方法，最适引物为CSV357F/R，探针CSV-CP-Probe（47 bp），引物和探针工作浓度分别为0.2和0.06μmol·L-1，温度为42℃，时间5 min。该方法可对SPCSV-wa进行特异性检测，与甘薯上其他常见病毒无交叉反应。RT-RPA-LFD最低可检测到总RNA稀释至10-4溶液，而RT-PCR最低检测到总RNA稀释至10-3溶液，RT-RPA-LFD灵敏度是RT-PCR的10倍。田间采集的22份甘薯样品经RT-PCR、RT-RPA和RT-RPA-LFD检测，均检出11份阳性样品，3种方法检测结果一致。28份试管苗样品的检测结果表明，RT-PCR和RT-RPA-LFD检测结果一致，均检出5份阳性样品。【结论】建立了SPCSV-wa的RT-RPA-LFD检测方法，该方法具有快速、简便、特异、灵敏、可视的特点，既可用于甘薯脱毒试管苗样品的病毒检测，也适用于基层单位田间甘薯病毒样品的现场快速检测。

关键词：甘薯褪绿矮化病毒西非株系逆转录酶重组酶聚合酶扩增侧向流层析快速检测甘薯

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保证瞬态性能的迭代学习控制

控制理论与应用 2014年第10期31卷 1295-1301页

作者：管海娃孙明轩齐丽强浙江工业大学信息工程学院浙江杭州310023 温州科技职业学院浙江温州325006

讨论一类不确定非线性系统的可保证瞬态性能的迭代学习控制问题.引入限定跟踪误差瞬态特性的界函数,通过误差转换方法,定义一个转换误差变量,将跟踪误差的保证瞬态特性问题转化为该误差变量的有界性问题.采用Lyapunov方法,设计迭代学习... 详细信息

讨论一类不确定非线性系统的可保证瞬态性能的迭代学习控制问题.引入限定跟踪误差瞬态特性的界函数,通过误差转换方法,定义一个转换误差变量,将跟踪误差的保证瞬态特性问题转化为该误差变量的有界性问题.采用Lyapunov方法,设计迭代学习控制器处理系统中参数和非参数不确定性.并且,采用完全限幅学习机制,保证转换误差变量的有界性和一致收敛性.从而既能得出系统输出在整个作业区间的完全跟踪性能,同时又能够保证跟踪误差在每次迭代的过程中具有保证的瞬态特性.仿真结果验证了所提控制方法的有效性.

关键词：收敛性迭代学习控制瞬态性能不确定非线性系统

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非参数不确定系统的有限时间迭代学习控制

自动化学报 2014年第7期40卷 1320-1327页

作者：齐丽强孙明轩管海娃浙江工业大学信息工程学院杭州310023 温州科技职业学院温州325006

针对任意初态情形,引入初始修正作用,研究一类非参数不确定时变系统能够达到实际完全跟踪性能的迭代学习控制方法.采用Lyapunov-like综合,设计迭代学习控制器处理不确定性时变系统非参数化问题,其中含有有限时间控制作用,以实现在预先... 详细信息

针对任意初态情形,引入初始修正作用,研究一类非参数不确定时变系统能够达到实际完全跟踪性能的迭代学习控制方法.采用Lyapunov-like综合,设计迭代学习控制器处理不确定性时变系统非参数化问题,其中含有有限时间控制作用,以实现在预先指定区间上的零误差跟踪.并且,运用完全限幅学习机制,保证闭环系统中各变量的一致有界性以及跟踪误差的一致收敛性.仿真结果表明了所提出控制方法的有效性.

关键词：迭代学习控制有限时间控制非参数化不确定时变系统

Tackling the tumor microenvironment： what challenge does it pose to anticancer therapies？

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Protein & Cell 2014年第11期5卷 816-826页

作者： Fei Chen Xinyi qi Min qian Yue Dai Yu Sun Institute of Health Sciences Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai 200031 China School of Medicine Shanghai Jiao Tong University Shanghai 200025 China VA Seattle Medical Center Seattle WA 98108 USA Department of Medicine University of Washington Seattle WA 98195 USA

Cancer is a highly aggressive and devastating disease, and impediments to a cure arise not just from cancer itself. Targeted therapies are difficult to achieve since the majority of cancers are more intricate than ever imagined. Mainstream methodologies including chemotherapy and radiotherapy as routine clinical regimens frequently fail, eventually leading to pathologies that are refractory and incurable. One major cause is the gradual to rapid repopulation of surviving cancer cells during intervals of multiple-dose administration. Novel stressresponsive molecular pathways are increasingly unmasked and show promise as emerging targets for advanced strategies that aim at both de novo and acquired resistance. We highlight recent data reporting that treatments particularly those genotoxic can induce highly conserved damage responses in non-cancerous constituents of the tumor microenvironment （TMEN）. Master regulators, including but not limited to NF-kB and C/EBP-β, are implicated and their signal cascades culminate in a robust, chronic and genome-wide secretory program, forming an activated TMEN that releases a myriad of soluble factors. The damage-elicited but essentially off target and cell non-autonomous secretory phenotype of host stroma causes adverse consequences, among which is acquired resistance of cancer cells. Harnessing signals arising from the TMEN, a pathophysiological niche frequently damaged by medical interventions, has the potential to promote overall efficacy and improve clinical outcomes provided that appropriate actions are ingeniously integrated into contemporary therapies. Thereby, anticancer regimens should be well tuned to establish an innovative clinical avenue, and such advancement will allow future oncological treatments to be more specific, accurate, thor- ough and personalized.

关键词： tumor microenvironment DNA damage,secretory phenotype therapy resistance genotoxicity,clinical intervention

幂律流体Wilhelmy吊片法动态湿润的理论与实验研究

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工程热物理学报 2018年第6期39卷 1186-1190页

作者：王雄闵琪张征明段远源清华大学核能与新能源技术研究院先进核能技术协同创新中心先进反应堆工程与安全教育部重点实验室北京100084 清华大学热科学与动力工程教育部重点实验室北京100084

幂律流体的黏度由于会随着剪切应变的变化而变化,其动态湿润机理比牛顿流体更加复杂。本文通过简化的二维吊片法模型,采用楔形区假设和黏性耗散理论建立了适用于幂律流体中剪切稀化流体吊片法湿润的表面张力驱动力和黏性滞动力动态平衡... 详细信息

幂律流体的黏度由于会随着剪切应变的变化而变化,其动态湿润机理比牛顿流体更加复杂。本文通过简化的二维吊片法模型,采用楔形区假设和黏性耗散理论建立了适用于幂律流体中剪切稀化流体吊片法湿润的表面张力驱动力和黏性滞动力动态平衡条件下的理论公式,并进行实验.通过对比,发现二维吊片法的理论公式与实验数据符合良好,并计算出楔形区截断长度的大致量级;分析了圆形三相接触线下该公式适用性较差的原因,定性解释了三相接触线形状对幂律型非牛顿流体湿润的影响.

关键词： Wilhelmy吊片法动态接触角幂律流体截断长度三相接触线形状