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Antioxidant Activity and Phenolic Compounds Content of Extracts from Ceratotheca sesamoides Endl and Striga hermonthica (Delille) Benth Used as Antheminthic in Burkina Faso
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作者 Dicko Amadou Kam Eric Sami +9 位作者 Hadidjatou Belem Konaté Almamy Tindano Basile Meda Roland Nâg-Tiéro Ahoua Angora Rémi Constant Koné Mamidou Witabouna Kaboré Adama Traoré Amadou Bayala Balé Tamboura Hamidou Hamadou 《Journal of Biosciences and Medicines》 CAS 2022年第11期203-213,共11页
The revaluation of medicinal plants in the veterinary pharmacopoeia is essential for the development of livestock in Burkina Faso. In order to justify the use of C. sesamoides and S. hermonthica in the treatment of ga... The revaluation of medicinal plants in the veterinary pharmacopoeia is essential for the development of livestock in Burkina Faso. In order to justify the use of C. sesamoides and S. hermonthica in the treatment of gastrointestinal parasitosis of small ruminants, a quantification of phenolic compounds as well as antioxidant activity and acute toxicité evaluation of both plants were performed. Acute toxicity was evaluated by administering a single dose of 2000 mg/kg body weight of aqueous extract of both plants to mice. The highest total polyphenol content for C. sesamo?des was obtained in the ethyl acetate fraction with 47.236 ± 2.57 mgEAG/100mg while that of S. hermonthica was 74.871 ± 2.57 mgEAG/100mg obtained with the n-butanol Fraction. The dichloromethane extract of S. hermonthica obtained the highest total flavonoid content with 7.31 ± 0.48 mgEQ/100 while the highest total flavonoid content of C. sesamo?des was obtained with ethyl acetate fraction with 5.4273 ± 0.35 mgEQ/100mg. The aqueous extract of C. sesamo?des obtained the highest content of condensed tannins with 3.028 ± 0.13 mgEAT/100mg. Both plant’s extracts did not show any signs of toxicity in NMRI mice after administration of the dose of 2000 mg/kg. The antioxidant activity by DPPH, FRAP and ABTS methods was good compared to those of Quercetin and Trolox taken as standard. 展开更多
关键词 C. sesamoides s. hermonthica Polyphénols content Flavonoids content Condensed Tannins Antioxidant Activity
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Effect of H_(2)S content on relative permeability and capillary pressure characteristics of acid gas/brine/rock systems:A review 被引量:1
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作者 Xiaoyan Zhang Qi Li +2 位作者 Mathias Simon Guodong Zheng Yongsheng Tan 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2022年第6期2003-2033,共31页
Geological storage of acid gas has been identified as a promising approach to reduce atmospheric carbon dioxide(CO_(2)),hydrogen sulfide(H_(2)S)and alleviate public concern resulting from the sour gas production.A goo... Geological storage of acid gas has been identified as a promising approach to reduce atmospheric carbon dioxide(CO_(2)),hydrogen sulfide(H_(2)S)and alleviate public concern resulting from the sour gas production.A good understanding of the relative permeability and capillary pressure characteristics is crucial to predict the process of acid gas injection and migration.The prediction of injection and redistribution of acid gas is important to determine storage capacity,formation pressure,plume extent,shape,and leakage potential.Herein,the existing experimental data and theoretical models were reviewed to gain a better understanding of the issue how the H_(2)S content affects gas density,gas viscosity,interfacial tension,wettability,relative permeability and capillary pressure characteristics of acid gas/brine/rock systems.The densities and viscosities of the acid gas with different H_(2)S mole fractions are both temperature-and pressure-dependent,which vary among the gas,liquid and supercritical phases.Water/acid gas interfacial tension decreases strongly with increasing H_(2)S content.For mica and clean quartz,water contact angle increases with increasing H_(2)S mole fraction.In particular,wettability reversal of mica to a H_(2)S-wet behavior occurs in the presence of dense H_(2)S.The capillary pressure increases with decreasing contact angle.At a given saturation,the relative permeability of a fluid is higher when the fluid is nonwetting.The capillary pressure decreases with decreasing interfacial tension at a given saturation.However,the existing datasets do not show a consistent link between capillary number and relative permeability.The capillary pressure decreases with increasing H_(2)S mole fraction.However,there is no consensus on the effect of the H_(2)S content on the relative permeability curves.This may be due to the limited availability of the relative permeability and capillary pressure data for acid gas/brine/rock systems;thus,more experimental measurements are required. 展开更多
关键词 Acid gas geological sequestration Relative permeability Capillary pressure H_(2)s content Wettability Interfacial tension
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The Water-Splashing Festival——Wet to One's Heart's Content
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《China Today》 2002年第4期26-27,共2页
关键词 The Water-splashing Festival Wet to One’s Heart’s content
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Influence of S Contents on the Hydrogen Blistering and Hydrogen Induced Cracking of A350LF2 Steel 被引量:4
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作者 Shu-qi Zheng Chang-feng Chen Li-qiang Chen 《Materials Sciences and Applications》 2011年第7期917-921,共5页
In the present work, the effects of chemical compositions on the hydrogen blistering and hydrogen induced cracking of A350LF2 steel with different S contents were studied. Four types of A350LF2 steels were evaluated b... In the present work, the effects of chemical compositions on the hydrogen blistering and hydrogen induced cracking of A350LF2 steel with different S contents were studied. Four types of A350LF2 steels were evaluated by immersing samples in H2S-saturated NACE solution. The hydrogen blistering, crack length rate(CLR), crack thickness rate(CTR) and crack sensitivity rate(CSR) were evaluated. The results show that there are many hydrogen blisters on the sample surface with S content of 0.021%, a few on the sample surface with S content of 0.019% and 0.012% and no one on the surface with S content of 0.002%. There were 12, 2 and 1 strips of cracks of longer than 0.3 mm on the evaluated cross sections with S content of 0.021%, 0.019% and 0.012%, respectively. There was no any crack in the sample with 0.002% S. The corrosion rate was also evaluated. The S content has no obvious influence on the corrosion rate. 展开更多
关键词 A350LF2 s content HYDROGEN BLIsTERING HYDROGEN Induced CRACKING
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Enhanced compactness and element distribution uniformity of Cu2ZnSnS4 thin film by increasing precursor S content
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作者 Hao Han Ji-Ning Wang +2 位作者 Jing Mi Xiao-Peng Liu Li-Jun Jiang 《Rare Metals》 SCIE EI CAS CSCD 2020年第3期256-261,共6页
Cu2ZnSnS4 thin films were prepared by cosputtering with Cu(or Cu2S),ZnS and SnS2 targets in this study.S amount in the precursor of Cu2ZnSnS4 thin film was verified by using Cu or Cu2S target.The effect of S amount in... Cu2ZnSnS4 thin films were prepared by cosputtering with Cu(or Cu2S),ZnS and SnS2 targets in this study.S amount in the precursor of Cu2ZnSnS4 thin film was verified by using Cu or Cu2S target.The effect of S amount in the precursor on the microstructure and element distribution of Cu2ZnSnS4 thin film was discussed.It was found that S content is sufficient in the precursor thin film using Cu2 S instead of Cu target.The microstructure,composition homogeneity,and secondary phase formation of the Cu2ZnSnS4 thin film are seriously affected by S amount in the precursor thin film.Namely,sufficient S can improve the crystallization and orientation of the precursor thin film and enhance the compactness as well as composition homogeneity of the Cu2ZnSnS4 thin film after sulfurization.Moreover,the secondary phase formation in Cu2ZnSnS4 thin film can be greatly inhibited by increasing S content in the precursor thin film. 展开更多
关键词 Cu2Znsns4 THIN film s content Diffusion
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基于PB设计和响应面法的CPS硫黄回收装置能量优化
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作者 尹晓云 朱进 +7 位作者 刘春艳 张锦涛 徐源 朱英如 苏明 孙月 孙杰 袁颖 《化工进展》 北大核心 2025年第S1期124-133,共10页
针对天然气净化厂硫黄回收装置能量产出较低的问题,本文提出了一种结合工艺过程模拟和数据统计分析的优化方法。首先,利用Plackett-Burman(PB)试验设计筛选出对硫黄回收装置能量产出影响显著的关键因素,再通过Box-Behnken design(BBD)... 针对天然气净化厂硫黄回收装置能量产出较低的问题,本文提出了一种结合工艺过程模拟和数据统计分析的优化方法。首先,利用Plackett-Burman(PB)试验设计筛选出对硫黄回收装置能量产出影响显著的关键因素,再通过Box-Behnken design(BBD)响应面试验对硫黄回收工艺进行优化,最后通过模拟分析验证了BBD响应面优化方法的有效性。结果表明:(1)酸气流量、酸气中H_(2)S含量和分流比对硫黄回收装置能量产出的影响最为显著,各因素的影响显著程度由大到小依次为酸气中H_(2)S含量>酸气流量>分流比;(2)确定的最佳工艺条件为,酸气流量90kmol/h、酸气中H_(2)S质量分数42%、分流比0.1,在此优化条件下,硫黄回收装置的能量产出可提高25.11%;(3)软件模拟值与模型预测值的相对误差仅为0.01%,所建立的硫黄回收装置能量产出模型预测准确可靠;(4)最优工艺参数经现场装置使用后的效果为,硫黄回收率为99.94%,平均能量产出达到2051.14kW。经过工艺参数优化后,硫黄回收装置的能量产出得到显著提升。 展开更多
关键词 硫黄回收 酸气流量 酸气中H_(2)s含量 分流比 PB设计 BBD响应面法 能量优化
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酒钢选矿厂关于原矿S含量影响调查及对策研究
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作者 赵国庆 涂威 《酒钢科技》 2025年第3期1-11,共11页
酒钢选矿厂面临综精S含量上升影响炼铁厂烧结工序,以及悬浮炉排放口烟气S含量超标影响环保的双重问题。本研究对2024年1-11月原料情况进行分析,周边矿S主要以黄铁矿形式存在,而桦树沟、黑沟矿S多以重晶石形式存在。选矿工艺可脱除重晶石... 酒钢选矿厂面临综精S含量上升影响炼铁厂烧结工序,以及悬浮炉排放口烟气S含量超标影响环保的双重问题。本研究对2024年1-11月原料情况进行分析,周边矿S主要以黄铁矿形式存在,而桦树沟、黑沟矿S多以重晶石形式存在。选矿工艺可脱除重晶石,黄铁矿仅部分被竖炉、悬浮炉焙烧脱除,周边矿用量增加是综精S上升的直接原因,黄铁矿分解是悬浮炉排放口烟气S上升的直接原因。 展开更多
关键词 硫(s)含量 黄铁矿 重晶石 选矿工艺 烟气排放s含量
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S-TRD工法机在高速公路改扩建深层软基就地固化处理中的应用
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作者 王新宇 《城市道桥与防洪》 2025年第10期315-319,共5页
就地固化作为一种软基处理方式,将固化材料和软土在原位进行搅拌,使之直接形成足够承载力的混合土体。传统的就地固化采用强力淤泥搅拌头进行原位搅拌,处治深度一般在4 m以内;而采用S-TRD工法机能够将处治深度提高至8 m,在此深度范围内... 就地固化作为一种软基处理方式,将固化材料和软土在原位进行搅拌,使之直接形成足够承载力的混合土体。传统的就地固化采用强力淤泥搅拌头进行原位搅拌,处治深度一般在4 m以内;而采用S-TRD工法机能够将处治深度提高至8 m,在此深度范围内可以完美地替代预应力管桩。在通过试验段施工后,从取芯检测、轻型动力触探和沉降监测等方面,逐一验证其施工合理性。经验证,确定S-TRD工法机可以作为8 m内深层软基的处理方式,其施工效果与水泥掺量有关,在6%~10%的水泥掺量范围内,在同等条件下,水泥掺量越多,施工后土基的承载力越高。 展开更多
关键词 就地固化 深层软基 s-TRD 水泥掺量
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铬天青S分光光度法快速分析钛合金中铝元素含量
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作者 钱安乐 李辉 +1 位作者 张俊美 姚佳人 《科技创新与生产力》 2025年第6期100-103,共4页
在pH=5~6范围内,以(1+1)硫酸溶解样品,过氧化氢掩蔽钛,六次甲基四胺溶液作为缓冲溶液,采用铬天青S分光光度法,测定钛合金中的铝元素含量。确定了比色波长为545 nm;显色液在15 min后即达到稳定状态,并可保持45 min。经验证,该试验方法的... 在pH=5~6范围内,以(1+1)硫酸溶解样品,过氧化氢掩蔽钛,六次甲基四胺溶液作为缓冲溶液,采用铬天青S分光光度法,测定钛合金中的铝元素含量。确定了比色波长为545 nm;显色液在15 min后即达到稳定状态,并可保持45 min。经验证,该试验方法的相对标准偏差(RSD)在1.97%~2.95%之间,回收率在95%~99%之间,获得了较满意的结果。 展开更多
关键词 钛合金 铝含量 铬天青 s分光光度法 比色分析
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L245NS钢在不同O_(2)含量的CO_(2)/H_(2)S/O_(2)体系中的腐蚀行为探究
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作者 周飞龙 唐鑫 +2 位作者 郭磊 廖柯熹 冷吉辉 《材料导报》 北大核心 2025年第18期201-207,共7页
某油田H区块稠油采用注多元热流体驱替方式开采,其采出物中含有CO_(2)、H_(2)S及O_(2)等气体,流经集输管道时会形成CO_(2)/H_(2)S/O_(2)三元腐蚀体系,且温度较高,管道系统内腐蚀问题严重。因此,针对现场采出物O_(2)含量变化大的特点,采... 某油田H区块稠油采用注多元热流体驱替方式开采,其采出物中含有CO_(2)、H_(2)S及O_(2)等气体,流经集输管道时会形成CO_(2)/H_(2)S/O_(2)三元腐蚀体系,且温度较高,管道系统内腐蚀问题严重。因此,针对现场采出物O_(2)含量变化大的特点,采用高温高压反应釜开展了L245NS钢在不同O_(2)含量(0%、1%、2%、3%)下的腐蚀行为研究,并分析了腐蚀产物的物相组成及微观形貌。结果表明:均匀腐蚀速率随着O_(2)含量的提高呈增长趋势,O_(2)参与了阴极去极化反应,同时氧化Fe^(2+)生成疏松多孔的高价铁氧化物,抑制FeCO_(3)的形成;O_(2)与H_(2)S间的交互作用增强,生成的S单质继续参与腐蚀反应,产物保护性能下降。局部腐蚀速率随着O_(2)含量的提高呈先增长后减小的趋势,O_(2)含量为2%时有极大值,高O_(2)含量抑制局部腐蚀。基于实验结果,集输管道选材时可选用更耐腐蚀的合金钢,若将该区块O_(2)含量控制在1%以下,可最大程度地减小钢材腐蚀。 展开更多
关键词 O_(2)含量 CO_(2)/H_(2)s/O_(2)体系 L245Ns 腐蚀机理
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基于S-P模型的南水河流域水质分析及污染预测研究
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作者 简倩韵 《粘接》 2025年第11期187-189,193,共4页
为应对因工业化和人口集聚导致的水质污染问题,研究以韶关市南水河流域为例,对南水水库取水后的该流域CODcr和NH_(3)-N进行了系统的水质预测分析。研究选用一维S-P模型,通过量化污染物在河流中的衰减规律,预测了不同工况下的水质时空分... 为应对因工业化和人口集聚导致的水质污染问题,研究以韶关市南水河流域为例,对南水水库取水后的该流域CODcr和NH_(3)-N进行了系统的水质预测分析。研究选用一维S-P模型,通过量化污染物在河流中的衰减规律,预测了不同工况下的水质时空分布特征。预测结果显示,2020年所有断面的CODcr和NH_(3)-N浓度均显著低于Ⅲ类水质标准限值;至2030年,虽受排污量增加影响,各断面污染物浓度有所上升,但总体仍控制在标准范围内。预测分析表明,南水水库工程取水后,南水河各河段水质仍可满足Ⅲ类水环境功能区划要求,可为类似流域的水质预测与污染防控提供科学参考。 展开更多
关键词 水质预测 南水河流域 s-P模型 化学需氧量 氨氮
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换剂工况下S Zorb装置原料汽油硫含量升高操作优化总结
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作者 黄伟辉 《炼油技术与工程》 2025年第9期7-9,共3页
介绍了某公司渣油加氢脱硫(RDS)装置停工换剂期间催化裂化汽油硫含量上升对S Zorb装置工艺参数调整的影响。该公司S Zorb装置在RDS装置换剂期间,原料汽油硫质量分数由163μg/g上升至287μg/g,严重影响了产品质量。通过调整反应温度、质... 介绍了某公司渣油加氢脱硫(RDS)装置停工换剂期间催化裂化汽油硫含量上升对S Zorb装置工艺参数调整的影响。该公司S Zorb装置在RDS装置换剂期间,原料汽油硫质量分数由163μg/g上升至287μg/g,严重影响了产品质量。通过调整反应温度、质量空速、吸附剂载硫量等参数,产品汽油硫质量分数满足该公司内控指标要求(不大于8μg/g),产品质量合格。在此期间,参数调整导致反应器过滤器ME101和再生烟气过滤器ME103的压差在短时间内快速升高,通过降低装置处理量和提高ME103的反吹氮气压力减缓了过滤器压差的上涨趋势。 展开更多
关键词 s Zorb装置 原料汽油 硫含量 反应温度 质量空速 循环氢流量 吸附剂载硫量 吸附剂硫容
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S含量及时效对Cu/Sn-8Zn-3Bi-xS/Cu钎料焊点可靠性的影响
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作者 帅歌旺 黄惠珍 《金属热处理》 CAS CSCD 北大核心 2024年第5期135-139,共5页
研究了S含量和时效对Cu/Sn-8Zn-3Bi-xSi/Cu钎料焊点可靠性的影响,采用润湿铺展面积评价Sn-8Zn-3Bi-xS钎料在Cu基板上的润湿性;通过搭接焊方法制备Cu/Sn-8Zn-3Bi-xS/Cu焊点,研究其90℃时效不同时间的力学性能;采用配有能谱的扫描电镜(SEM... 研究了S含量和时效对Cu/Sn-8Zn-3Bi-xSi/Cu钎料焊点可靠性的影响,采用润湿铺展面积评价Sn-8Zn-3Bi-xS钎料在Cu基板上的润湿性;通过搭接焊方法制备Cu/Sn-8Zn-3Bi-xS/Cu焊点,研究其90℃时效不同时间的力学性能;采用配有能谱的扫描电镜(SEM)对焊点断面形貌和成分进行观察和分析;采用X射线衍射仪(XRD)对焊点界面形成的金属间化合物进行物相分析。结果表明,添加S能够改善Sn-8Zn-3Bi-xS钎料在Cu基板上的润湿性,S含量为0.05wt%时润湿面积最大。时效时间相同时,钎料剪切强度随S含量的增加先增大后减小,S含量为0.05wt%时钎料具有最大的剪切强度;S含量相同时,钎料剪切强度随时效时间的延长先增大后减小,时效时间为4 h时剪切强度最大。添加S不改变焊点界面金属间化合物的成分组成。 展开更多
关键词 sn-Zn无铅钎料 s含量 时效 可靠性
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Spend to Your Heart’s Content
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作者 WANG JUN 《Beijing Review》 2009年第7期29-29,共1页
The government believes that boosting domestic consumption this year will help it achieve its 8-percent economic growth
关键词 spend to Your Heart’s content
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Corrosion Behavior of 110S Tube Steel in Environments of High H_2S and CO_2 Content 被引量:25
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作者 LI W en-fei ZHOU Yan-jun XUE Yan 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2012年第12期59-65,共7页
The corrosion behavior of the 110S tube steel in the environments of high H2 S and CO2 content was inves- tigated by using a high-temperature and high-pressure autoclave, and the corrosion products were characterized ... The corrosion behavior of the 110S tube steel in the environments of high H2 S and CO2 content was inves- tigated by using a high-temperature and high-pressure autoclave, and the corrosion products were characterized by scanning electron microscopy and X ray diffraction technique. The results showed that all of the corrosion products under the test conditions mainly consisted of different types of iron sulfides such as pyrrhotite of Fe0.95 S, mackinaw- ite of FeS0.9, Fe0. 985 S and FeS, and the absence of iron carbonate in the corrosion scales indicated that the corrosion process was controlled by H2S corrosion. The corrosion rate of the 110S steel decreased firstly and then increased with the rising of temperature. The minimum corrosion rate occurred at 110 ℃. When the H2 S partial pressure PH2s below 9 MPa, the corrosion rate declined with the increase of PH2s. While over 9 MPa, a higher PH2s resulted in a faster corrosion process. With the increasing of the CO2 partial pressure, the corrosion rate had an increasing trend. The morphologies of the corrosion scales had a good accordance with the corrosion rates. 展开更多
关键词 110s tube steel high H2s and Co2 content environment corrosion rate corrosion scale
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How “Made-in-China” Boosts U.S.Employment-An Empirical Analysis of “U.S.Content” in China’s Exports of Manufactured Goods
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作者 王孝松 周嘉辰 翟光宇 《China Economist》 2015年第1期32-42,共11页
This paper aims to examine the specific ways in which China's exports of manufactured goods to the United States boost the U.S. job market. Using the OECD STAN Bilateral Trade Database by Industry and End-use Categor... This paper aims to examine the specific ways in which China's exports of manufactured goods to the United States boost the U.S. job market. Using the OECD STAN Bilateral Trade Database by Industry and End-use Category to calculate the share of U.S. intermediate products used in the manufactured goods China exports to the U.S., this paper finds that the "U.S. content" in China's exports of manufactured goods to the U.S. increases with the technology content of the goods and shows a decreasing trend over time. From 2006 to 2010, the average "US. content" in China's exports of manufactured goods to the U.S. was 1%, and such content in China's exports of high-end manufactured goods was 1.6%. On this basis and using the employment-output ratio in the U.S. Employment Demand Matrix, this paper concludes that as many as 1.71 million jobs have been created by the U.S. intermediate products used in China's exports of manufactured goods to the U.S. during the same period. Thus, the development of Sino-U.S. trade has a positive impact on the job market in the U.S.. By contrast, instead of improving the employment situation in the U.S., the RMB appreciation proposed by the U.S. might even have a negative effect. 展开更多
关键词 made in China employment promotion U.s. content vertical specialization
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General Contents for CHINA'S REFRACTORIES (1992 - 2011)
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《China's Refractories》 CAS 2012年第1期55-71,共17页
关键词 sIALON General contents for CHINA’s REFRACTORIEs
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General Contents for CHINA’S REFRACTORIES(Vol.28,2019)
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《China's Refractories》 CAS 2019年第4期53-54,共2页
关键词 General contents for CHINA’s REFRACTORIEs Vol.28 2019
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General Contents for CHINA'S REFRACTORIES(Vol.21,2012)
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《China's Refractories》 CAS 2012年第4期54-54,共1页
关键词 General contents for CHINA’s REFRACTORIEs Vol.21
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Vital Contents of China's Foreign Trade in 2008
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《China's Foreign Trade》 2008年第23期67-71,共5页
关键词 CO PR RE Vital contents of China’s Foreign Trade in 2008
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