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原油中C_(26)-C_(28)三芳甾烷相对含量计算方法及其应用

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石油实验地质 2016年第5期38卷 692-697页

作者：张宝收李美俊赵青王铁冠张科肖中尧黄少英中国石油塔里木油田分公司勘探开发研究院新疆库尔勒841000 中国石油大学(北京)油气资源与探测国家重点实验室北京102249

三芳甾烷(TAS)是规则甾烷芳构化产物,其中C_(26)-C_(28)三芳甾烷系列稳定分布于原油和烃源岩有机质中。在常规色谱-质谱分析得到的芳烃馏分(m/z 231)质量色谱图上,由于C2620R和C2720S TAS异构体共流出而不能确定3种不同碳数三芳甾烷的... 详细信息

三芳甾烷(TAS)是规则甾烷芳构化产物,其中C_(26)-C_(28)三芳甾烷系列稳定分布于原油和烃源岩有机质中。在常规色谱-质谱分析得到的芳烃馏分(m/z 231)质量色谱图上,由于C2620R和C2720S TAS异构体共流出而不能确定3种不同碳数三芳甾烷的相对含量,无法建立类似于C27-C29规则甾烷的相对含量三角图,从而使三芳甾烷在油气地球化学中的应用受到限制。以塔里木盆地台盆区古生界代表性原油样品为例,建立了三芳甾烷相对含量三角图,并用北部湾盆地福山凹陷古近系原油进行了验证。结果表明:该区存在2种不同来源的原油,可以划分为2个不同的原油族群,而来自福山凹陷古近系的原油具有不同的C_(26)-C_(28)三芳甾烷组成特征,原油族群的划分也得到其他分子地球化学证据的支持。在高成熟的轻质油和凝析油中,规则甾烷系列由于浓度低而很难由常规的色谱-质谱分析技术进行检测和鉴定,三芳甾烷由于相对较高的热稳定性而稳定存在,因此可代替规则甾烷用于油-油对比和原油族群划分。

关键词：三芳甾烷原油族群色谱—质谱分析塔里木盆地北部湾盆地

不同β-受体激动剂添加模式对肉牛血液生化指标和激素水平的影响

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中国畜牧兽医 2017年第9期44卷 2638-2643页

作者：刘佳张凯龙瑞军张军民赵青余王洪亮赵福忠兰州大学草地农业科技学院兰州730030 中国农业科学院北京畜牧兽医研究所农业部华北动物遗传资源与营养科学观测站北京100193 兰州大学生命科学学院兰州730030 黑龙江省农垦科学院畜牧兽医研究所哈尔滨150038

试验旨在研究不同β-受体激动剂添加模式对肉牛血液生化指标和激素水平的影响。选取15头体况良好、体重相近(257.9kg±33.3kg)的西门塔尔肉牛,随机分为3组,每组5头。对照组饲喂基础日粮;试验Ⅰ组添加莱克多巴胺,添加剂量为670.0μg/kg体... 详细信息

试验旨在研究不同β-受体激动剂添加模式对肉牛血液生化指标和激素水平的影响。选取15头体况良好、体重相近(257.9kg±33.3kg)的西门塔尔肉牛,随机分为3组,每组5头。对照组饲喂基础日粮;试验Ⅰ组添加莱克多巴胺,添加剂量为670.0μg/kg体重;试验Ⅱ组添加莱克多巴胺、沙丁胺醇和克伦特罗的混合物,添加剂量分别为223.3、50.0、5.3μg/kg体重。给药期28d,停药期28d。结果表明,与对照组相比,在给药第28天时,试验Ⅰ组肉牛血浆中游离脂肪酸(FFA)浓度显著降低(P0.05)。综合上述试验结果,肉牛血浆中的FFA可作为β-受体激动剂潜在的生物标志物,可通过对其的监测来监管β-受体激动剂在肉牛生产环节中的非法使用。

关键词： β-受体激动剂肉牛血液生化指标激素水平

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新疆部分地产淡水鱼中稀土元素含量调查

中国卫生检验杂志 2018年第5期28卷 611-613页

作者：雒婉霞赵清荣王庆国杨勤德新疆维吾尔自治区疾病预防控制中心新疆乌鲁木齐830001

目的了解新疆部分地产淡水鱼中稀土元素的含量,分析鱼体中稀土元素的分布情况。方法在新疆巴州、博州、阿勒泰3个淡水鱼主产区采集100份地产淡水鱼,依据《2015年国家食品污染和有害因素风险监测工作手册》中,动植物性食品中稀土元素电... 详细信息

目的了解新疆部分地产淡水鱼中稀土元素的含量,分析鱼体中稀土元素的分布情况。方法在新疆巴州、博州、阿勒泰3个淡水鱼主产区采集100份地产淡水鱼,依据《2015年国家食品污染和有害因素风险监测工作手册》中,动植物性食品中稀土元素电感耦合离子体质谱法测定的标准操作程序进行检测。结果 100份地产淡水鱼稀土元素总量(以稀土氧化物总量计,下同)在0.002 mg/kg^1.007 mg/kg,其中97%(97/100)的样品稀土元素总量>0.100 mg/kg。3个产区样品中稀土元素总量差异无统计学意义(P>0.05)。但轻稀土含量和检出率均高于重稀土,差异有统计学意义(P<0.05)。结论本次调查的地产淡水鱼中含有一定量的稀土元素,但总体水平不高。同时鱼体中轻稀土的高含量和高检出率表明淡水鱼对稀土的富集能力有所差异,对重稀土的富集能力相对较弱。

关键词：稀土元素淡水鱼调查新疆

复合材料K/T型接头真空辅助成型工艺树脂流动研究

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玻璃钢／复合材料 2017年第9期 97-100,72页

作者：赵清华王长春岳广全刘建光张嘉振中国商飞北京民用飞机技术研究中心民用飞机结构与复合材料北京市重点实验室北京102211 不详

城市的现代化进程促进了大跨度结构的应用,用于结构间的连接接头需要具有良好的力学、耐疲劳和耐腐蚀性能。先进复合材料以优异的性能成为理想的接头材料,但高昂的制造成本限制了其应用。对基于真空辅助成型(VARTM)工艺制造K/T型接头时... 详细信息

城市的现代化进程促进了大跨度结构的应用,用于结构间的连接接头需要具有良好的力学、耐疲劳和耐腐蚀性能。先进复合材料以优异的性能成为理想的接头材料,但高昂的制造成本限制了其应用。对基于真空辅助成型(VARTM)工艺制造K/T型接头时的树脂流动过程进行了研究,通过考察四种可能树脂注模方式所需注模时间及流动前锋的信息确定合理的工艺方式;并将模拟结果与相应试验结果对比分析,两者表现出良好的一致性。采用复合材料接头一体化制造模具制造出K/T型接头,并组装了典型复合材料桁架结构。试验结果表明,模拟所得注模方式可实现复合材料K/T型接头的低成本工艺制造,避免了由传统试错法确定注模方式带来的高成本。

关键词：复合材料 K/T型接头 VARTM工艺树脂流动数值模拟

Detrended cross-correlation analysis of electroencephalogram

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Chinese Physics B 2012年第2期21卷 577-580页

作者： wang Jun zhao Da-qing Image Processing and Image Communications Key Laboratory School of Geography and Biological InformationNanjing University of Posts&TelecommunicationNanjing 210003China

In the paper we use detrended cross-correlation analysis （DCCA） to study the electroencephalograms of healthy young subjects and healthy old subjects. It is found that the cross-correlation between different leads of a healthy young subject is larger than that of a healthy old subject. It was shown that the cross-correlation relationship decreases with the aging process and the phenomenon can help to diagnose whether the subject＇s brain function is healthy or not.

关键词： detrended cross-correlation analysis electroencephalogram brain function aging process

Robust Navier-Stokes method for predicting unsteady flowfield and aerodynamic characteristics of helicopter rotor

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Chinese Journal of Aeronautics 2018年第2期31卷 214-224页

作者： Qijun zhao Guoqing zhao Bo wang qing wang Yongjie SHI Guohua XU National Key Laboratory of Rotorcraft Aeromechanics Nanjing University of Aeronautics and Astronautics

A robust unsteady rotor flowfield solver CLORNS code is established to predict the complex unsteady aerodynamic characteristics of rotor flowfield. In order to handle the difficult problem about grid generation around rotor with complex aerodynamic shape in this CFD code,a parameterized grid generated method is established, and the moving-embedded grids are constructed by several proposed universal methods. In this work, the unsteady Reynolds-Averaged Navier-Stokes（RANS） equations with Spalart-Allmaras are selected as the governing equations to predict the unsteady flowfield of helicopter rotor. The discretization of convective fluxes is accomplished by employing the second-order central difference scheme, third-order MUSCL-Roe scheme, and fifth-order WENO-Roe scheme. Aimed at simulating the unsteady aerodynamic characteristics of helicopter rotor, the dual-time scheme with implicit LU-SGS scheme is employed to accomplish the temporal discretization. In order to improve the computational efficiency of holecells and donor elements searching of the moving-embedded grid technology, the ‘‘disturbance diffraction method＂ and ‘‘minimum distance scheme of donor elements method＂ are established in this work. To improve the computational efficiency, Message Passing Interface（MPI） parallel method based on subdivision of grid, local preconditioning method and Full Approximation Storage（FAS） multi-grid method are combined in this code. By comparison of the numerical results simulated by CLORNS code with test data, it is illustrated that the present code could simulate the aerodynamic loads and aerodynamic noise characteristics of helicopter rotor accurately.

关键词： Aerodynamic characteristicsHelicopter rotor Moving-embedded grid Navier-Stokes equations Upwind schemes

Laser direct writing of flexible multifunctional airflow sensors on the Kevlar fabric

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Nano Research 2025年第1期18卷 443-454页

作者： Wei wang Zi-qing Chen Yong-Qi Li Yu-Long wang Mei-Chen Liu Yun-Bo Ruan Yang Zhang Shu-Juan Liu Qiang zhao College of Electronic and Optical Engineering and College of Flexible Electronics(Future Technology) Nanjing University of Posts and TelecommunicationsNanjing 210023China State Key Laboratory of Organic Electronics and Information Displays and Jiangsu Key Laboratory for Biosensors Institute of Advanced Materials(IAM)Nanjing University of Posts and TelecommunicationsNanjing 210023China Zhe Jiang Topsun Logistic Control CO. LTD.Yuhuan 317600China Department of Rehabilitation Medicine School of Acupuncture-Moxibustion and Tuina and School of Health Preservation and RehabilitationNanjing University of Chinese MedicineNanjing 210023China

The growing interest in flexible devices has emerged as a global trend due to their advantages in flexibility,lightweight structure,and wearability,addressing the limitations of traditional *** wearable airflow sensors have been previously reported,the development of flexible fabric-based airflow sensors capable of functioning in environments with open flames—critical for fire rescue operations—has yet to be explored,largely due to the poor fire resistance of conventional *** this work,we first present a flexible,wearable,and multifunctional airflow sensor with excellent fire-resistant properties,fabricated through a simple direct laser writing *** sensor maintains airflow detection capabilities even in the presence of open ***,the fabrication of fabric-based sensors involves complex procedures such as carbon materials doping or vapor-phase deposition,leading to lengthy preparation cycles and high ***,fabric-based devices are inherently prone to *** address these challenges,we introduce twice-vertical laser-induced graphene(TVLIG)as a sensitive and reliable component for fire-resistant airflow *** resulting TVLIG/Kevlar fabric can be integrated into various garments,particularly protective suits,to form sensitive and fire-resistant airflow sensors capable of detecting airflow velocity and direction in both two-dimensional(2D)and three-dimensional(3D)spaces during fire ***,the TVLIG patterns can be expanded to multifunctional platforms,such as glucose detection for injured individuals,offering further applications in rescue *** functional expansion reduces the burden on rescue personnel and streamlines device *** its outstanding sensing capabilities,fire resistance,and expandability,the developed flexible airflow sensor shows great potential for various real-world rescue scenarios,promising advancements in wearable sensing technology for rescue enginee

关键词： flexible airflow sensor direct laser writing twice-vertical laser-induced graphene fire accident rescue Kevlar fabric

Edge Engineering of MoS2 Nanoribbons as High Performance Electrode Material for Na-ion Battery： A First-Principle Study

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Chinese Journal of Chemistry 2017年第6期35卷 896-902页

作者： Jianbin wang qing zhao Jun Chen Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education) College of Chemistry Nankai University Tian/in 300071 China Collaborative Innovation Center of Chemical Science and Engineering Nankai University Tianjin 300071 China

Substantial effort has been made to search for electrode materials of Na-ion batteries with high energy/power density. The application of S-saturated zigzag MoS2 nanoribbons （MoSzNRs） for Na-ion batteries has been explored through density function theory （DFT）. The theoretical maximum specific capacity reaches 386.4 mAh,g t via dou- ble-side and special edge adsorption mode. The electronic structure reveals that there exists charge transfer between Na and MoS2NRs. The diffusion barrier on MoS2NRs （0.17 eV） is much lower than that of bulk MoS2 （1.15 eV）, indicating an excellent diffusion kinetics, in addition, the S-edge in MoS2NRs plays a key role. Firstly, the Mo edge was half saturated by S, which helps to stabilize the MoS2NRs as well as offer more intercalation sites for Na. On the other hand, Na migrates much faster on the S edge route in MoS2NRs. Our computational results show that S-saturated MoSzNRs exhibit a great potential as electrode materials for Na-ion batteries with high performance.

关键词： MoS2 nanoribbons Na-ion battery S-saturated edge effect density function theory

Highly-Efficient Aerodynamic Optimal Design of Rotor Airfoil Using Viscous Adjoint Method

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Transactions of Nanjing University of Aeronautics and Astronautics 2017年第2期34卷 134-142页

作者： Wu Qi zhao Qijun wang qing National Key Laboratory of Science and Technology on Rotorcraft Aeromechanics Nanjing University of Aeronautics and Astronautics

In order to overcome the efficiency problem of the conventional gradient-based optimal design method,a highly-efficient viscous adjoint-based RANS equations method is applied to the aerodynamic optimal design of hovering rotor *** C-shaped body-fitted mesh is firstly automatically generated around the airfoil by solving the Poisson equations,and the Navier-Stokes(N-S)equations combined with Spalart-Allmaras(S-A)one-equation turbulence model are used as the governing equations to acquire the reliable flowfield ***,according to multi-constrained characteristics of the optimization of high lift/drag ratio for hovering rotor airfoil,its corresponding adjoint equations,boundary conditions and gradient expressions are newly *** these bases,two representative rotor airfoils,NACA0012 airfoil and SC1095 airfoil,are selected as numerical examples to optimize their synthesized aerodynamic characteristics about lift/drag ratio in hover,and better aerodynamic performance of optimal airfoils are obtained compared with the ***,the new designed rotor with the optimized rotor airfoil has better hover aerodynamic characteristics compared with the baseline *** contrast to the baseline airfoils optimized by the finite difference method,it is demonstrated that the adjoint optimal algorithm itself is practical and highly-efficient for the aerodynamic optimization of hover rotor airfoil.

关键词： rotor airfoil viscous adjoint method aerodynamic characteristics multi-constraints computational fluid dynamics(CFD) highly efficiency