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PEI溶液紫外吸收光谱检测油气田硫化氢气体 被引量:2
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作者 唐东林 张琪 +1 位作者 柯志军 王瞧 《分析测试学报》 CAS CSCD 北大核心 2018年第6期749-753,共5页
建立了一种基于聚乙烯亚胺(PEI)溶液的紫外(UV)吸收光谱检测油气田硫化氢(H2S)气体浓度的方法。利用PEI结构中的氨基可与H2S气体反应的特性,测定通入H2S气体前后PEI溶液的UV吸收光谱,并分析了UV光谱吸收峰在230、365 nm附近的吸光度变... 建立了一种基于聚乙烯亚胺(PEI)溶液的紫外(UV)吸收光谱检测油气田硫化氢(H2S)气体浓度的方法。利用PEI结构中的氨基可与H2S气体反应的特性,测定通入H2S气体前后PEI溶液的UV吸收光谱,并分析了UV光谱吸收峰在230、365 nm附近的吸光度变化与气体浓度的关系。采用标准浓度的H2S气体样品进行浓度标定实验,建立了H2S气体浓度与吸光度之间的关系模型。实验结果表明:通入高纯度H2S气体时,PEI溶液的UV光谱在230 nm和365 nm处均出现较强吸收峰;通入较低浓度H2S气体时,UV光谱只在230 nm处出现吸收峰,该吸收峰附近的吸光度与H2S气体浓度间存在线性关系(相关系数为0.970 6),系统对H2S气体浓度的检出限可达15.39 mg/m3。基于PEI溶液的UV吸收光谱检测法可为油气田H2S气体浓度的快速、准确测定提供参考。 展开更多
关键词 聚乙烯亚胺 紫外吸收光谱 硫化氢气体 有机聚合物 精确测量
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永磁同步电机永磁体分块对涡流损耗的影响分析 被引量:5
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作者 刘朋鹏 张琪 +2 位作者 何彪 黄苏融 陈世军 《电机与控制应用》 2018年第6期56-61,共6页
逆变器供电的永磁同步电机(PMSM)中电子器件的高频开关会产生高频的电流时间谐波,进而引起永磁体涡流损耗的显著增加。给出了一种考虑电流时间谐波的永磁体涡流损耗计算的解析式,详细分析了永磁体尺寸和透入深度与涡流损耗之间的关系,... 逆变器供电的永磁同步电机(PMSM)中电子器件的高频开关会产生高频的电流时间谐波,进而引起永磁体涡流损耗的显著增加。给出了一种考虑电流时间谐波的永磁体涡流损耗计算的解析式,详细分析了永磁体尺寸和透入深度与涡流损耗之间的关系,并通过一个理想的3D模型进行验证。以1台逆变器供电的48槽8极PMSM为例进行涡流损耗仿真计算,结果表明:永磁体合理的分块数可以有效减少涡流损耗。 展开更多
关键词 电流时间谐波 涡流损耗 永磁体分块 集肤效应 解析法
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Organic carbon stock in topsoil of Jiangsu Province, China, and the recent trend of carbon sequestration 被引量:46
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作者 PANGen-xing LILian-qing +4 位作者 zhangqi WANGXu-kui SUNXing-bin XUXiao-bo JIANGDing-an 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2005年第1期1-7,共7页
Data collection of soil organic carbon(SOC) of 154 soil series of Jiangsu, China from the second provincial soil survey and of recent changes in SOC from a number of field pilot experiments across the province were co... Data collection of soil organic carbon(SOC) of 154 soil series of Jiangsu, China from the second provincial soil survey and of recent changes in SOC from a number of field pilot experiments across the province were collected. Statistical analysis of SOC contents and soil properties related to organic carbon storage were performed. The provincial total topsoil SOC stock was estimated to be 0 1 Pg with an extended pool of 0 4 Pg taking soil depth of 1 m, being relatively small compared to its total land area of 101700 km 2 One quarter of this topsoil stock was found in the soils of the Taihu Lake region that occupied 1/6 of the provincial arable area. Paddy soils accounted for over 50% of this stock in terms of SOC distribution among the soil types in the province. Experimental data from experimental farms widely distributed in the province showed that SOC storage increased consistently over the last 20 years despite a previously reported decreasing tendency during the period between 1950—1970 The evidence indicated that agricultural management practices such as irrigation, straw return and rotation of upland crops with rice or wheat crops contributed significantly to the increase in SOC storage. The annual carbon sequestration rate in the soils was in the range of 0 3—3 5 tC/(hm 2·a), depending on cropping systems and other agricultural practices. Thus, the agricultural production in the province, despite the high input, could serve as one of the practical methods to mitigate the increasing air CO 2 展开更多
关键词 soil organic carbon soil carbon stock agricultural practice carbon sequestration paddy soil China
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A New Base-6 FFT Algorithm 被引量:2
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作者 zhangqi ZHOUWei-xian 《Semiconductor Photonics and Technology》 CAS 2003年第1期23-25,共3页
A new FFT algorithm has been deduced, which is called the base-6 FFT algorithm. The amount for calculating the DFT of complex sequence of N =2 r by the base-6 FFT algorithm is M r( N )=14/3· N log 6 N -4 N +4 for... A new FFT algorithm has been deduced, which is called the base-6 FFT algorithm. The amount for calculating the DFT of complex sequence of N =2 r by the base-6 FFT algorithm is M r( N )=14/3· N log 6 N -4 N +4 for multiplication operation of real number and A r( N )=23/3· N log 6 N -2 N +2 for addition operation of real number. The amount for calculating the DFT of real sequence is a half of it with the complex sequence. 展开更多
关键词 数字信号处理器 DSP 叶立叶变换 DFT 算法
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Phase Transition for a Mixed Spin-1/2 and Spin-sB System with a Transverse CrystalField
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作者 JIANGWei XIAOGui-Bin +2 位作者 WEIGuo-Zhu DUAn zhangqi 《Communications in Theoretical Physics》 SCIE CAS CSCD 2004年第1期131-134,共4页
The critical behaviors of a mixed spin-1/2 and spin-sB Ising system with a transverse crystal field are studiedby use of the effective-field theory with correlations. The effect of the transverse crystal field on tran... The critical behaviors of a mixed spin-1/2 and spin-sB Ising system with a transverse crystal field are studiedby use of the effective-field theory with correlations. The effect of the transverse crystal field on transition temperaturesis investigated numerically for the honeycomb (z = 3) and square (z = 4) lattices. The results show that there is notricritical point for the system. 展开更多
关键词 相位转变 横向晶体场 相图 哈密顿算符 传输温度 晶体材料
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Effects of Biaxial Crystal-Field on Magnetic System
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作者 JIANGWei WEIGuo-Zhu +1 位作者 DUAn zhangqi 《Communications in Theoretical Physics》 SCIE CAS CSCD 2003年第4X期503-506,共4页
The spin-1 Ising model with biaxiM crystal-field on the honeycomb lattice is investigated by using the effective-field theory with self-spin correlations and the differential operator technique. The effects of biaxial... The spin-1 Ising model with biaxiM crystal-field on the honeycomb lattice is investigated by using the effective-field theory with self-spin correlations and the differential operator technique. The effects of biaxial crystal-field described by two uniaxial anisotropy parameters Dx and Dy on the phase transition and specific heat and susceptibility are studied numerically. Some interesting results are observed in the system such as tricritical behavior depending sensitively on the strength of the biaxial crvstal-field. 展开更多
关键词 铁磁系统 三重脉冲行为 二轴晶体场 磁化系数 有效场理论 单离子各向异性规则
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Studies on the extraction of uranium (VI) by bis (hexylsulfinyl) ethane
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作者 YANGYan-Zhao zhangqi +2 位作者 ZENGShan BAOLi-Ping SUNSi-Xiu 《Nuclear Science and Techniques》 SCIE CAS CSCD 2003年第4期261-264,共4页
The extraction of uranium (Ⅵ) by bis(hexylsulfinyl)ethane(BHxSE) in nitric acid aqueous solution hasbeen investigated. The extracted species appeared to be UO2(NO3)2@2BHxSE. Influences of nitric acid concentration,Na... The extraction of uranium (Ⅵ) by bis(hexylsulfinyl)ethane(BHxSE) in nitric acid aqueous solution hasbeen investigated. The extracted species appeared to be UO2(NO3)2@2BHxSE. Influences of nitric acid concentration,NaNO3 concentration, Na2C2O4 concentration and temperature on the extraction equilibrium were investigated andthe thermodynamic functions of the extraction reaction were obtained. 展开更多
关键词 萃取方法 硝酸 热力学方程 亚砜
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Study of Properties of Mixed Ferro-Ferrimagnetic Ising Compounds with (AxB1-x)yC
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作者 XINZi-Hua WEIGuo-Zhu +1 位作者 LIANGYa-Qiu zhangqi 《Communications in Theoretical Physics》 SCIE CAS CSCD 2004年第6X期831-834,共4页
The magnetic properties of the mixed ferro-ferrimagnetic compounds with (AxB1-x)yC, where A, B, and C are three different magnetic ions and form three different sublattices, are studied by using the standard mean-fiel... The magnetic properties of the mixed ferro-ferrimagnetic compounds with (AxB1-x)yC, where A, B, and C are three different magnetic ions and form three different sublattices, are studied by using the standard mean-field theory. The phase diagram which is related to experimental work of molecule-based ferro-ferrimagnet (NiⅡxMn1Ⅱ-x)1.5[CrⅢ(CN)6]· zH2O is obtained. The magnetization curves, internal energy, and specific heat of the same mixed (Ax B1- x) y C system are also investigated. 展开更多
关键词 混合亚-铁氧磁材料 相位图 加热比 内能
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Bragg Grating Formation in B/Ge Codoped Optical Fibers
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作者 SANGXin-zhu YUChong-xiu +2 位作者 ChuPakL LaiRobust zhangqi 《Semiconductor Photonics and Technology》 CAS 2005年第1期5-8,共4页
A 2-cm long Bragg grating with reflectivity of~99.95% in B/Ge codoped optical fiber without hydrogen loading was created by phase-mask method with a pulsed KrF excimer laser at 248 nm. DC and AC components of refract... A 2-cm long Bragg grating with reflectivity of~99.95% in B/Ge codoped optical fiber without hydrogen loading was created by phase-mask method with a pulsed KrF excimer laser at 248 nm. DC and AC components of refractive index change were analyzed by monitoring transmission spectrum evolution during the writing process of fiber Bragg grating. The relations of the evolution of center wavelength and reflectivity with number of pulses were respectively investigated. 展开更多
关键词 B/Ge掺杂光纤 光纤布拉格光栅 折射率 相位屏蔽
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电极孔隙结构对锂空气电池性能影响机制研究
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作者 曾建邦 张琪 +3 位作者 单丰武 林德阳 张月娅 胡超 《华东交通大学学报》 2022年第4期94-104,共11页
以非水系锂空气电池为例,基于Comsol软件平台开发了一维电化学模型,该模型较文献中的模型计算结果更加接近实验测试结果。利用该模型探讨了空气电极孔隙率及其分布、制备空气电极固体骨架所用多孔碳颗粒尺寸、空气电极固体骨架和孔相扭... 以非水系锂空气电池为例,基于Comsol软件平台开发了一维电化学模型,该模型较文献中的模型计算结果更加接近实验测试结果。利用该模型探讨了空气电极孔隙率及其分布、制备空气电极固体骨架所用多孔碳颗粒尺寸、空气电极固体骨架和孔相扭曲率对非水系锂空气电池性能的影响规律,发现随着空气电极孔隙率增大,由其制备而成的非水系锂空气电池放电电压平台和容量越高;若沿着厚度方向的空气电极孔隙率随机,且其平均孔隙率与具有恒定孔隙率的空气电极孔隙率相同,则相对于后者,由前者制备而成非水系锂空气电池放电电压平台和容量更高;随着构筑空气电极固体骨架的多孔碳颗粒尺寸不断减小,非水系锂空气电池放电平台不断升高,但放电容量却不断降低;随着空气电极孔相或固体骨架扭曲率的逐渐增大,非水系锂空气电池放电平台和容量均呈不断降低的趋势。 展开更多
关键词 锂空气电池 空气电极 孔隙结构 电化学模型
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Time course and evaluation of neurological deficits after focal cerebral ischemia in mice
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作者 YUYue-ping WEIEr-qing +3 位作者 XUQiu-qin ZHUChao-yang ZHUYe-fei zhangqi 《中国药理通讯》 2004年第2期35-35,共1页
AIM : To observe time course of neurological deficits after focal cerebral ischemia in mice, and to confirm the quantitative and objective method we developed for evaluating neurological deficits. METHODS: Focal cereb... AIM : To observe time course of neurological deficits after focal cerebral ischemia in mice, and to confirm the quantitative and objective method we developed for evaluating neurological deficits. METHODS: Focal cerebral ischemia was induced by middle cerebral artery occlusion. The neurological deficits were assessed 6 h, 12 h, 24 h, or 1-7 d after ischemia. 展开更多
关键词 评价方法 神经疾病 大脑 脑动脉栓塞 时间进程
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Therapeutic effect of pranlukast, a cysteinyl leukotriene receptor antagonist, on focal cerebral ischemia in mice
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作者 XUQiu-Qin WEIEr-Qing +3 位作者 YUYue-Ping zhangqi ZHANGShi-Hong ZHUChao-Yang 《中国药理通讯》 2004年第2期39-39,共1页
AIM: To determine whether pranlukast (ONO-1078 ), a cysteinyl leukotriene receptor antagonist, possesses therapeutic effect when administered after focal cerebral ischemia in mice. METHODS: Persistent focal cerebral ... AIM: To determine whether pranlukast (ONO-1078 ), a cysteinyl leukotriene receptor antagonist, possesses therapeutic effect when administered after focal cerebral ischemia in mice. METHODS: Persistent focal cerebral ischemia was induced by middle cerebral artery occlusion, pranlukast and edaravone, a positive control drug, were ip injected 1, 6 展开更多
关键词 细胞受体 脑缺血 大鼠 药理实验
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股骨近端N三角理论及股骨近端仿生髓内钉(PFBN)的设计理念 被引量:25
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作者 朱燕宾 陈伟 +4 位作者 叶丹丹 张奇 吕红芝 郑占乐 张英泽 《中华老年骨科与康复电子杂志》 2021年第5期257-259,共3页
Ward三角由Ward于1838年提出,是当时了解股骨近端解剖结构及力学传导特点的一个重要发现。事实上,股骨近端远不止有一个Ward三角,而是由数个肉眼可观的“宏观三角”和数量庞大的“微观三角”构成,这就是“张氏N三角理论”。基于“张氏N... Ward三角由Ward于1838年提出,是当时了解股骨近端解剖结构及力学传导特点的一个重要发现。事实上,股骨近端远不止有一个Ward三角,而是由数个肉眼可观的“宏观三角”和数量庞大的“微观三角”构成,这就是“张氏N三角理论”。基于“张氏N三角理论”,并在分析股骨近端骨折术后内固定物并发症的原因后,课题组设计并研发出更符合人体力学特点的股骨近端仿生髓内钉(PFBN)。本文旨在通过详细阐述“张氏N三角理论”及其指导下研发的PFBN的结构和力学特点,为其临床应用的科学性和合理性提供研究思路。 展开更多
关键词 转子间骨折 股骨近端 Ward三角 仿生髓内钉 张氏N三角理论
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Identification of Mesoproterozoic zircons in a Triassic dolerite from the Liaodong Peninsula, Northeast China 被引量:23
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作者 YANGJinhui WUFuyuan +2 位作者 ZHANGYanbin zhangqi SimonA.Wilde 《Chinese Science Bulletin》 SCIE EI CAS 2004年第18期1958-1962,共5页
Thick Neoproterozoic strata are widespread in the Dalian region, Liaodong Peninsula, Northeast China. SHRIMP zircon U-Pb dating of dolerite intruded into Neo-proterozoic strata gives its emplacement age as 211±2 ... Thick Neoproterozoic strata are widespread in the Dalian region, Liaodong Peninsula, Northeast China. SHRIMP zircon U-Pb dating of dolerite intruded into Neo-proterozoic strata gives its emplacement age as 211±2 Ma. However, abundant 0.9—1.1 Ga zircons are identified in the dolerite. The age of 1125±38 Ma corresponds with the Grenvillian collisional event. The zircons of 904±15 Ma ages have high Th/U ratios (1.31—2.25) and magmatic oscillatory zones, being possibly related to later magmatism induced during amalgamation of Rodinia. 展开更多
关键词 中元古代 锆石 三叠纪 粗粒玄武岩 辽东半岛 华北地区 U-PB年龄 测定
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在晚期肺癌患者中实施个性化心理护理对心理状态与生活质量的改善作用 被引量:1
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作者 赵晶 韩永莉 张起 《黑龙江中医药》 2022年第4期315-317,共3页
目的:探讨在晚期肺癌患者中实施个性化心理护理对心理状态与生活质量的改善作用。方法:将2018年1月至2020年7月在我院治疗的100例晚期肺癌患者随机分为对照组(n=50)及观察组(n=50)。仅对观察组使用个性化心理护理干预。观察两组的焦虑... 目的:探讨在晚期肺癌患者中实施个性化心理护理对心理状态与生活质量的改善作用。方法:将2018年1月至2020年7月在我院治疗的100例晚期肺癌患者随机分为对照组(n=50)及观察组(n=50)。仅对观察组使用个性化心理护理干预。观察两组的焦虑自评量表(SAS)评分、抑郁自评量表(SDS)评分及生活质量情况。结果:观察组患者的SAS、SDS评分更低,观察组患者的生理健康、精神健康评分更高,上述差异在统计学上均有意义(p<0.05)。结论:个性化心理护理可显著改善晚期肺癌患者的心理状态,并提高患者的生活质量。 展开更多
关键词 晚期肺癌 个性化心理护理 心理状态 生活质量
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哀牢山里人间事,且邀青山话桑麻
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作者 戴钰欣 何黛娜 +2 位作者 张琪 黄思梦 韦诗誉 《人类居住》 2019年第3期62-65,共4页
序站在哀牢山畔极目远眺,是层层叠叠静如止水的梯田,一片片流光溢彩的层面隐现在云海中。将目光定格在掩映间的蘑菇房,听蝉响、鸟鸣、虫语奏出村庄的故事。白云深处有人家作为一个古朴的小村落,阿者科至今不通公路,一条青石路将村头的... 序站在哀牢山畔极目远眺,是层层叠叠静如止水的梯田,一片片流光溢彩的层面隐现在云海中。将目光定格在掩映间的蘑菇房,听蝉响、鸟鸣、虫语奏出村庄的故事。白云深处有人家作为一个古朴的小村落,阿者科至今不通公路,一条青石路将村头的寨神林与村尾的磨秋场相连。初入阿者科已是落日时分,天空中的云霞在金光的辉映下晕染成一幅油画。炊烟悠然,袅袅飘荡在蘑菇屋上方,群山宁静悠远,云上生活此刻伊始。 展开更多
关键词 哈尼人 寨神林 哀牢山 哈尼古歌 哈尼族
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