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HPC海量存储系统Pass-Through访问策略研究 被引量:2
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作者 朱平 《计算机研究与发展》 EI CSCD 北大核心 2013年第8期1667-1673,共7页
为了解决海量信息处理中实时访问中的"I/O墙"的问题,提高海量信息分布式存储系统的性能,提出了一种基于高性能计算(high performance computing,HPC)的存储部件新型访问策略.首先,分析传统访问模型存在的问题;其次,研究存储... 为了解决海量信息处理中实时访问中的"I/O墙"的问题,提高海量信息分布式存储系统的性能,提出了一种基于高性能计算(high performance computing,HPC)的存储部件新型访问策略.首先,分析传统访问模型存在的问题;其次,研究存储部件直通路模式的工作机理,建立存储系统分解为多层次、分布式的模型,根据不同的层次和映射策略实现存储空间物理地址、缓存地址、存储系统逻辑空间地址的连续映射;第三,分析直通路访问模式下的存储路径时间开销;第四,在模拟环境下存储部件访问的性能测试,在实际采用该策略的应用系统中进行验证.通过验证测试结果表明,该方法能有效提高存储系统的性能,能够不断满足海量信息处理实时需要. 展开更多
关键词 高性能计算 海量存储系统 存储部件直通路 存储层次映射 存储策略
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Correlation between pass-through flux of cobalt target and microstructure and magnetic properties of sputtered thin films
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作者 Xiu-Lan Xu Qian-Ming Huang +8 位作者 Guo-Nan Feng Gang Han Qi-Xun Guo Xiao-Dong Xiong Xin He Jun-Feng Luo Rong-Ming Wang Chun Feng Guang-Hua Yu 《Rare Metals》 SCIE EI CAS CSCD 2021年第4期975-980,共6页
Cobalt thin films were deposited on silicon substrates by magnetron sputtering two commercial cobalt targets with different pass-through fluxes(PTFs).The influences of PTF on the magnetic properties of sputtered thin ... Cobalt thin films were deposited on silicon substrates by magnetron sputtering two commercial cobalt targets with different pass-through fluxes(PTFs).The influences of PTF on the magnetic properties of sputtered thin films were investigated.The results indicate that under the same sputtering conditions,cobalt thin film deposited by Co target with high PTF(84.21%) has lower remanence ratio(0.65),while cobalt thin film prepared by Co target with low PTF(69.13%) has higher remanence ratio(0.87).Through introducing an external magnetic field parallel to the film surface during sputtering processes,both the remanence ratios of cobalt thin films prepared by the two targets can be enhanced to approach 1.High-resolution transmission electron microscopy(HRTEM) images show that in the absence of the external magnetic field during sputtering,cobalt thin film deposited by the target with high PTF is randomly oriented in crystallographic orientations,which is due to that Co atoms have no enough time to migrate and diffuse on substrate and the atomic stacking is disordered.It is worth mentioning that crystallographic orientations of cobalt thin film deposited by target with low PTF are relatively consistent,resulting in relatively higher remanence ratio.In addition,HRTEM analysis indicates that the external magnetic field during sputtering drives the Co grains to arrange in a regular order with(002) orientation,leading to the improvement in remanence ratios. 展开更多
关键词 Sputtering target pass-through flux Thin film MICROSTRUCTURE
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DIgi率先在工业自动化设备服务器提供串行Pass-Through功能
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《可编程控制器与工厂自动化(PLC FA)》 2004年第6期26-26,共1页
关键词 工业自动化设备 服务器 pass-through PLC DIgi公司
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“多效穴”探微
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作者 李杰 王强 文颖娟 《陕西中医药大学学报》 2026年第2期6-10,共5页
近几年腧穴的功效、主治作用及共性机制研究取得重要进展。通过分析四肢部、头面部、躯干部多效穴的主治和功效特点,并从经络理论、神经-内分泌免疫、行正气三方面探讨多效穴具有多类主治功效的作用机制。在临床应用针灸时,应多关注多效... 近几年腧穴的功效、主治作用及共性机制研究取得重要进展。通过分析四肢部、头面部、躯干部多效穴的主治和功效特点,并从经络理论、神经-内分泌免疫、行正气三方面探讨多效穴具有多类主治功效的作用机制。在临床应用针灸时,应多关注多效穴,避免功效相似的多个腧穴重复选用,功效重叠,相互抑制,出现“饱和效应”。 展开更多
关键词 多效穴 单效穴 同效穴 三效穴 根结标本 经脉所过 主治所及
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Pass-through Effects of Global Commodity Prices on China's Inflation:An Empirical Investigation 被引量:8
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作者 Ligang Liu Andrew Tsang 《China & World Economy》 SCIE 2008年第6期22-34,共13页
The present paper uses a two-step approach to estimate the pass-through effects of changes in international commodity prices and the RMB exchange rate on domestic consumer price inflation in China. We first estimate t... The present paper uses a two-step approach to estimate the pass-through effects of changes in international commodity prices and the RMB exchange rate on domestic consumer price inflation in China. We first estimate the pass-through effects of international commodity prices on producer prices and then estimate the pass-through effects of producer price inflation on consumer price inflation. We find that a l O-percent increase in international commodity prices would lead to China' s producer prices increasing by 1.2 percent 3 months later, which in turn would increase China' s domestic inflation by 0.24 percent over the same period. However, a 10-percent appreciation of the RMB exchange rate against the US dollar would help to reduce increases in producer prices by 4.4 percent over the following 3 months, which in turn would lead to a 0. 89-percent decline in consumer price inflation over the same period. Our findings suggest that appreciation of the RMB in an environment of rising global commodity prices and a weak US dollar could be an effective instrument to help contain inflation in China. 展开更多
关键词 China commodity price exchange rate pass-through
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Interest Rate Pass-through in a Dual-track System:Evidence from China 被引量:7
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作者 Xuejun Jin Frank M.Song +1 位作者 Yizhong Wang Yi Zhong 《China & World Economy》 SCIE 2014年第4期21-39,共19页
Using the Phillips-Loretan approach, this paper verifies the degree and speed of pass- through and rigidity of different interest rates in China, as well as the response of private loan interest rates to other interes... Using the Phillips-Loretan approach, this paper verifies the degree and speed of pass- through and rigidity of different interest rates in China, as well as the response of private loan interest rates to other interest rates during 2002-2012. The results indicate that the long-term pass-through from the interbank offered rates and deposit and loan interest rates to the treasury bond rate is incomplete, but that the long-term pass-through to private loan interest rates is overshooting. The long-term pass-through from the deposit and loan interest rates to the overnight interbank offered rate is incomplete, while that to the interbank offered rates of other maturities is complete. The short-term passthrough and adjustment speed of interest rates exhibit asymmetry. Therefore, before considering a full liberalization of interest rates, it is important to further enhance the competition of the financial system and the function of different interest rate systems, such as the interhank market and bond market. 展开更多
关键词 interest rate liberalization interest rate pass-through RIGIDITY
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Exchange Rate Pass-through in China 被引量:3
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作者 Chang Shu Xiaojing Su 《China & World Economy》 SCIE 2009年第1期33-46,共14页
During the second half of 2007 and early part of 2008 when there were intense inflationary pressures in China, RMB appreciation was advocated as a means of helping to curb inflation. The effectiveness of appreciation ... During the second half of 2007 and early part of 2008 when there were intense inflationary pressures in China, RMB appreciation was advocated as a means of helping to curb inflation. The effectiveness of appreciation in controlling inflation depends on the impact of exchange rate movements on import and domestic prices. Our analysis finds fairly large and speedy exchange rate pass-through (ERPT) to import prices: 50 and 60percent for the short run and long run, respectively. However, the degree of ERPT decreases along the price chain from upstream to downstream prices. ERPT for consumer prices, the most downstream prices, is much milder and has substantial lags. A 10-percent rise in the nominal effective exchange rate will dampen consumer prices by 1.1 percent within a year, with very little pass-through in the first half year, and by 2.0percent over the long run. These findings, particularly the ERPT to consumer prices, suggest that RMB appreciation can help to reduce inflationary pressures over the longer term. However, it is unlikely to provide rapid relief to the current round of high inflation because of the long lags in ERPZ. The RMB needs to strengthen in effective terms to exert the desired dampening impact on prices. 展开更多
关键词 exchange rate pass-through import prices INFLATION RMB appreciation
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Low Inflation,Pass-through,and a Discrete Inflation-targeting Framework for Monetary Policy in China 被引量:2
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作者 Chengsi Zhang 《China & World Economy》 SCIE 2007年第2期59-73,共15页
The performance of inflation in China over the past few decades has been remarkable. This paper characterizes the statistical nature of the inflation series in China over the past quarter of a century and presents an ... The performance of inflation in China over the past few decades has been remarkable. This paper characterizes the statistical nature of the inflation series in China over the past quarter of a century and presents an interesting scenario of large decline in inflation passthrough accompanied with low inflation since the end of the 1990s. How should monetary policy in China be conducted under these new economic conditions? We propose a discrete inflation-targeting framework for monetary policy, which is likely to be suitable for the regime of low inflation and inflation pass-through. The advantages and caveats of adopting such a framework are also discussed. 展开更多
关键词 inflation pass-through inflation targeting monetary policy
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Interest rate liberalization and pass-through of monetary policy rate to bank lending rates in China 被引量:3
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作者 Jingya Li Ming-Hua Liu 《Frontiers of Business Research in China》 2019年第2期212-230,共19页
We examine whether the effectiveness of the monetary policy rate transmission differs before and after interest rate liberalization in China using the autoregressive distributed lag (ARDL) bound test and an error corr... We examine whether the effectiveness of the monetary policy rate transmission differs before and after interest rate liberalization in China using the autoregressive distributed lag (ARDL) bound test and an error correction model (ECM). The results show that after liberalization the mark-up is lower, and both the Iong-run and shortrun interest rate pass-through has become faster and more complete. We attribute our findings to the ongoing reforms of China's banking system, which has improved the competitiveness of Chinese commercial banks. 展开更多
关键词 INTEREST RATE pass-through INTEREST RATE LIBERALIZATION China Autoregressive distributed lag (ARDL) bound test Error correction model (ECM)
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China's Share of US Imports and Exchange Rate Pass-through to US Import Prices 被引量:1
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作者 Jianhuan Zhou Donghun Kim 《China & World Economy》 SCIE 2011年第3期87-104,共18页
The present paper investigates the effect of China's share of US imports on the aggregatelevel exchange rate pass-through to US import prices over the period from January 1999 to December 2008. The paper also focuses... The present paper investigates the effect of China's share of US imports on the aggregatelevel exchange rate pass-through to US import prices over the period from January 1999 to December 2008. The paper also focuses on the post-reform period, after 2005, allowing greater ftexibility of the RMB to explore the change in the role of the Chinese import share in determining the trend in the US exchange rate pass-through. Evidence reveals that China's share of US imports has a negative effect on the exchange rate pass-through. However, this negative effect has been moderated to a negligible level since China's exchange rate reform. An important implication is that the exchange rate flexibility of the RMB has been raised to a significant level may no longer cause distortion in the US competitive environment and prevent the USA from adjusting current accounts. 展开更多
关键词 China's share exchange rate pass-through US import prices
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Exchange Rate Pass-through to China's Export Price: A Product-level Investigation
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作者 Jian Han Yanzhi Shen 《China & World Economy》 SCIE 2016年第2期48-67,共20页
Exchange rate movement usually results in changes in the production costs of exporting firms, and, therefore, the prices and the quantity of traded products. The present paper constructs a theoretical model to demonst... Exchange rate movement usually results in changes in the production costs of exporting firms, and, therefore, the prices and the quantity of traded products. The present paper constructs a theoretical model to demonstrate that export products with higher productivity, or with larger market share, or of higher quality will experience a less complete passthrough. Using the six-digit harmonized system export data from the CEPII database over the period of 2000 to 2013, the present paper examines how product heterogeneity affects the exchange rate pass-through of Chinese exports. The empirical results show that the most competitive Chinese export products, or those least affected by exchange rate risks, are those of higher quality, with higher technological complexity and at the high end of the international value chain. Therefore, Chinese exporting firms should pay more attention to improving export quality and upgrading technology to better cope with exchange rate risks and to enjoy more bargaining power in the international market. 展开更多
关键词 exchange rate pass-through export competitiveness product heterogeneity
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隧洞穿越活动断裂带衬砌结构力学响应研究
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作者 贾正滴 卢玉斌 +1 位作者 蒋继彬 欧阳林 《云南水力发电》 2026年第2期57-60,共4页
西南山区水利工程项目隧洞面临活动断裂带地质条件下易受断层错动影响的工程难题,以滇中引水二期配套工程晋宁干线柴东隧洞2号施工支洞穿越普渡河断裂F27构造带及其影响带为背景,采用FLAC3D建立三维地质力学模型,通过数字模拟与理论分... 西南山区水利工程项目隧洞面临活动断裂带地质条件下易受断层错动影响的工程难题,以滇中引水二期配套工程晋宁干线柴东隧洞2号施工支洞穿越普渡河断裂F27构造带及其影响带为背景,采用FLAC3D建立三维地质力学模型,通过数字模拟与理论分析相结合的方法,分析断层不同位移速率下衬砌结构的动态响应。研究结果表明,活断层错动会导致衬砌局部应力集中,通过柔性接头与加强配筋相结合的设计方案,可有效解决隧洞穿越活动断裂施工期及运行期的安全问题。 展开更多
关键词 隧洞 穿越 活动断裂 衬砌结构 力学响应
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海积地层中并行公路与地铁隧道穿越复杂桥梁桩基影响分析研究
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作者 梁万金 《福建建筑》 2026年第2期68-74,共7页
以深圳望海路快速公路隧道及深圳地铁13号线区间隧道穿越深圳湾大桥工程为背景,采用有限元软件Midas GTS,对隧道施工全过程进行三维数值模拟分析。通过模拟计算,分析海积地层中并行公路与地铁隧道穿越深圳湾大桥施工引起桥梁变形的规律... 以深圳望海路快速公路隧道及深圳地铁13号线区间隧道穿越深圳湾大桥工程为背景,采用有限元软件Midas GTS,对隧道施工全过程进行三维数值模拟分析。通过模拟计算,分析海积地层中并行公路与地铁隧道穿越深圳湾大桥施工引起桥梁变形的规律;同时通过分析变形规律,确定合理的施工参数。通过模拟得出,在复杂环境下的有限元方法能较好地实现隧道穿越桥梁施工的影响分析。表明增设桩基与承台能很好地限制桥梁沉降;在隧道穿越桥梁主要影响区增设必要的顶、侧加固,能减小桥梁沉降及桩基的水平位移;在盾构推进的过程中,合理控制注浆压力,亦能很好地协调桥桩的沉降与水平变形。 展开更多
关键词 隧道 穿越桥桩 加固 有限元分析
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泵送支柱支护技术在工作面过空巷应用中的数值模拟
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作者 赵福兴 吴怀国 王瑞杰 《煤炭技术》 2026年第3期59-65,共7页
为进一步研究泵送支柱支护技术在工作面过空巷期间的矿压显现规律和泵送支柱的支柱作用效果,采用三维有限差分软件FLAC^(3D),对工作面过空巷期间的空巷围岩变形规律和煤柱受力特点进行了数值模拟分析,模拟结果表明:在工作面过空巷期间,... 为进一步研究泵送支柱支护技术在工作面过空巷期间的矿压显现规律和泵送支柱的支柱作用效果,采用三维有限差分软件FLAC^(3D),对工作面过空巷期间的空巷围岩变形规律和煤柱受力特点进行了数值模拟分析,模拟结果表明:在工作面过空巷期间,泵送支柱起到了保障空巷围岩稳定和保护煤柱的作用,使空巷围岩变形、塑性区范围、锚杆索轴力和煤柱垂直应力峰值均有所减小。以潞安化工集团新元矿9110综采工作面为工程背景,将泵送支柱支护技术进行了工业性应用,现场矿压观测结果表明:该技术应用效果良好,空巷在工作面回采期间整体变形较小,顶底下沉量不超过150 mm,两帮移近量不超过400 mm,泵送支柱无碎裂、倒塌现象,支架整体受力较为稳定,顶板无破断现象。 展开更多
关键词 泵送支柱 工作面过空巷 矿压观测 数值模拟
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超高效液相色谱-串联质谱法测定猪肉中38种有机紫外吸收剂含量
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作者 李苑雯 兰程程 +2 位作者 吴炜亮 吕冰 李敬光 《食品安全质量检测学报》 2026年第4期281-289,共9页
目的建立超高效液相色谱-串联质谱法(ultra performance liquid chromatography-tandem mass spectrometry,UPLC-MS/MS)同时测定猪肉中38种有机紫外吸收剂(organic ultraviolet absorbents,OUVAs)的方法。方法经乙腈提取、通过式固相萃... 目的建立超高效液相色谱-串联质谱法(ultra performance liquid chromatography-tandem mass spectrometry,UPLC-MS/MS)同时测定猪肉中38种有机紫外吸收剂(organic ultraviolet absorbents,OUVAs)的方法。方法经乙腈提取、通过式固相萃取柱EMR-Lipid净化目标物,随后以甲醇-0.1%甲酸水溶液和甲醇-0.1%氨水溶液两种体系梯度洗脱,采用Acquity UPLC BEH C_(18)色谱柱(100 mm×2.1 mm,1.7μm)分离。质谱采用电喷雾正/负离子源电离,多反应监测模式采集数据,内标法靶向定量。结果38种OUVAs在相应质量浓度范围内呈现良好线性关系(r^(2)≥0.9958),检出限为0.002~0.300μg/kg,定量限为0.005~0.900μg/kg。空白基质中3个添加水平的加标回收率为61.2%~128.2%,相对标准偏差均小于等于11.8%。应用该方法对19份市售猪肉进行检测,共检出17种OUVAs。样品中ΣOUVAs含量范围为4.28~30.39μg/kg。结论该方法便携高效、重现性好、覆盖目标物种类多,适用于猪肉中38种OUVAs的痕量测定。 展开更多
关键词 有机紫外吸收剂 超高效液相色谱-串联质谱法 EMR-Lipid 通过式固相萃取 猪肉
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通过式固相萃取净化-超高效液相色谱-串联质谱法快速测定部分动物源性食品中46种杀虫剂残留
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作者 肖泳 曾小明 +4 位作者 李政 袁列江 邓航 谢叔娥 潘照 《食品研究与开发》 2026年第1期134-144,共11页
该研究建立通过式固相萃取结合超高效液相色谱-串联质谱法快速测定部分动物源性食品中46种杀虫剂残留的分析方法。样品加水分散后,用乙腈提取,HMR-Lipid固相萃取柱净化,经XSelect HSS T3色谱柱分离,以甲醇和水为流动相进行梯度洗脱,基... 该研究建立通过式固相萃取结合超高效液相色谱-串联质谱法快速测定部分动物源性食品中46种杀虫剂残留的分析方法。样品加水分散后,用乙腈提取,HMR-Lipid固相萃取柱净化,经XSelect HSS T3色谱柱分离,以甲醇和水为流动相进行梯度洗脱,基质匹配标准曲线外标法定量。结果表明,46种杀虫剂在各自线性范围内线性关系良好,相关系数大于0.995,定量限为1.0~10.0μg/kg;以猪肉、猪肾、鸡蛋、牛奶为基质,在定量限、10倍定量限、50倍定量限加标水平下的回收率为65%~110%,相对标准偏差为1.9%~10.6%。该方法高效便捷,定量准确,适用于畜禽肉及内脏、蛋类、生乳等动物源性食品中46种杀虫剂残留的快速定量检测。 展开更多
关键词 杀虫剂 动物源性食品 通过式固相萃取净化 超高效液相色谱-串联质谱 快速测定
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超高水头抽水蓄能电站泥沙输移特性与过机含沙量研究
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作者 陆森 邓贵铭 万钦梅 《红水河》 2026年第1期69-73,89,共6页
针对超高水头抽水蓄能电站的泥沙磨损问题,以广西桂林抽水蓄能电站(额定水头732 m)为例,开展泥沙输移与过机含沙量预测研究。基于邻近水文站资料推求悬移质输沙模数,采用推悬比系数法及沙莫夫公式计算推移质输沙量,并量化上游梯级水库... 针对超高水头抽水蓄能电站的泥沙磨损问题,以广西桂林抽水蓄能电站(额定水头732 m)为例,开展泥沙输移与过机含沙量预测研究。基于邻近水文站资料推求悬移质输沙模数,采用推悬比系数法及沙莫夫公式计算推移质输沙量,并量化上游梯级水库的拦沙效应。综合运用张瑞瑾公式、丁君松公式、水流挟沙力公式及一维泥沙数学模型,多方法计算过机含沙量。结果表明:电站下水库多年平均悬移质输沙量为13 907 t,推移质输沙量为1234 t;推荐过机含沙量取值为28.6 g/m3,满足高水头机组安全运行规范要求。研究可为超高水头抽水蓄能电站的泥沙设计及水轮机防护提供关键依据。 展开更多
关键词 抽水蓄能电站 泥沙输移 过机含沙量 高水头 一维泥沙数学模型 梯级水库 水轮机磨损
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超高效液相色谱-串联质谱法同时测定蛋制品中23种兽药残留
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作者 张永菊 侯广月 +3 位作者 周莉莉 徐志娇 卞英芳 曹琦 《化学分析计量》 2026年第3期81-88,114,共9页
建立超高效液相色谱-串联质谱法同时测定蛋制品中23种兽药残留。样品采用0.5%甲酸-乙腈溶液提取,提取液冷冻后经PRiME HLB小柱净化,浓缩后采用ACQUITY UPLC BEH C_(18)色谱柱分离,以甲醇-0.1%甲酸溶液为流动相进行梯度洗脱,在多反应监... 建立超高效液相色谱-串联质谱法同时测定蛋制品中23种兽药残留。样品采用0.5%甲酸-乙腈溶液提取,提取液冷冻后经PRiME HLB小柱净化,浓缩后采用ACQUITY UPLC BEH C_(18)色谱柱分离,以甲醇-0.1%甲酸溶液为流动相进行梯度洗脱,在多反应监测模式下,正离子扫描,以基质匹配外标法或内标法定量。23种兽药的质量浓度在各自范围内与色谱峰面积线性关系良好,相关系数均不小于0.995,方法检出限为0.03~0.2μg/kg,定量限为0.1~0.5μg/kg。样品平均回收率为71.1%~117%,测定结果的相对标准偏差为1.7%~12%(n=6)。采用所建方法对随机购买的150批次蛋制品进行检测,其中8批次蛋制品中检出恩诺沙星、氧氟沙星和甲氧苄啶等化合物。该方法适用于蛋制品中23种兽药残留的快速筛查。 展开更多
关键词 超高效液相色谱-串联质谱法 兽药残留 蛋制品 通过式固相萃取
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通过式固相萃取-超高效液相色谱-串联质谱法测定沉积物中草铵膦、草甘膦及其代谢物 被引量:3
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作者 杨霄 谢仲桂 +3 位作者 李小玲 索纹纹 陈相艺 万译文 《色谱》 北大核心 2025年第2期155-163,共9页
建立了通过式固相萃取-超高效液相色谱-串联质谱法测定沉积物中草铵膦、草甘膦及其6种代谢物(3-甲基磷酸亚基丙酸、N-乙酰草铵膦、氨甲基膦酸、N-乙酰氨甲基膦酸、N-乙酰草甘膦、N-甲基草甘膦)的方法。样品采用4%(体积分数)氨水溶液提取... 建立了通过式固相萃取-超高效液相色谱-串联质谱法测定沉积物中草铵膦、草甘膦及其6种代谢物(3-甲基磷酸亚基丙酸、N-乙酰草铵膦、氨甲基膦酸、N-乙酰氨甲基膦酸、N-乙酰草甘膦、N-甲基草甘膦)的方法。样品采用4%(体积分数)氨水溶液提取,提取液经PRiME HLB固相萃取柱净化,过0.22μm聚醚砜滤膜后供超高效液相色谱-串联质谱测定。目标化合物使用Metrosep A Supp 5阴离子色谱柱(150 mm×4.0 mm,5μm)分离,以水和200 mmol/L碳酸氢铵溶液(含0.05%(v/v)氨水)作为流动相进行梯度洗脱,在电喷雾离子源(ESI)、负离子扫描和多反应监测(MRM)模式下进行测定,基质匹配外标法定量。结果表明,草铵膦、草甘膦及其代谢物在15 min内即可完成色谱分离,色谱峰形良好,响应值高,目标化合物在2.0~200.0μg/L范围内线性关系良好,相关系数均大于0.995。草铵膦、3-甲基磷酸亚基丙酸、N-乙酰草铵膦、N-乙酰氨甲基膦酸、N-乙酰草甘膦、N-甲基草甘膦的检出限为5μg/kg,定量限为20μg/kg;草甘膦、氨甲基膦酸的检出限为10μg/kg,定量限为30μg/kg。以空白沉积物为基质样品,在3个加标水平(定量限、5倍定量限和10倍定量限)下,低有机质含量的沉积物中目标化合物的平均回收率为78.5%~107%,相对标准偏差为1.32%~14.7%(n=6);高有机质含量的沉积物中目标化合物的平均回收率为76.4%~113%,相对标准偏差为2.60%~11.2%(n=6)。采用本方法对池塘、湖泊、水库、河流等不同类型的沉积物样品进行测定,结果显示,湖泊、水库、河流沉积物样品中未检出草铵膦、草甘膦及其代谢物,1个池塘沉积物样品中检出草甘膦和氨甲基膦酸,检出含量分别为31.7μg/kg和52.3μg/kg。本研究建立的方法具有简单、快速、绿色环保、准确度和灵敏度高、重复性好等优势,适用于沉积物中草铵膦、草甘膦及其代谢物的快速检测,为研究其在沉积物中的残留特征和环境行为提供了技术支持。 展开更多
关键词 超高效液相色谱-串联质谱 通过式固相萃取 草铵膦 草甘膦 代谢物 沉积物 非衍生化
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不确定性冲击对中国实体经济的非对称传递效应——基于总量和结构双重视角的经验证据
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作者 刘金全 袁月 杨光 《吉林大学社会科学学报》 北大核心 2025年第4期63-78,283,共17页
文章采用高维因子模型分离并识别来自中国经济、金融和政策层面的不确定性冲击;在此基础上,从总量和结构的双重视角出发,基于NARDL模型考察中国各类不确定性冲击对实体经济增长以及三次产业经济增长的非对称传递效应。研究结果表明:从... 文章采用高维因子模型分离并识别来自中国经济、金融和政策层面的不确定性冲击;在此基础上,从总量和结构的双重视角出发,基于NARDL模型考察中国各类不确定性冲击对实体经济增长以及三次产业经济增长的非对称传递效应。研究结果表明:从总量视角来看,中国经济、金融不确定性上升的经济抑制效果明显强于不确定性下降的经济提振效果,短期内政策不确定性的上升在一定程度上能够起到刺激经济增长的作用,而长期内政策不确定性则表现出明显的“逆周期性”;从结构视角来看,不同层面的不确定性对三次产业经济存在显著的非均衡性影响,经济、金融不确定性的上升会导致产业供需结构的扭曲和产业经济衰退的加剧,而劳动密集型产业则表现出对政策不确定性冲击的抵御作用。 展开更多
关键词 经济不确定性 金融不确定性 政策不确定性 非对称传递效应 NARDL模型
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