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Economic Competitiveness of China and the US:Comparison,Dynamic Change and Global Position 被引量:2
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作者 倪鹏飞 王海波 《China Economist》 2017年第4期2-31,共30页
Research of competitiveness of China and the United States is of great significance to enhancing China's economic competitiveness and achieving the objective of national rejuvenation. By creating a competitiveness fr... Research of competitiveness of China and the United States is of great significance to enhancing China's economic competitiveness and achieving the objective of national rejuvenation. By creating a competitiveness framework and a system of heterogeneous indicators, this paper investigates the competitiveness of China and the US in terms of current status, historic change and global environment. Our research led to the following findings: core factors determine the level of competitiveness for China and the US; the national competitiveness of both countries is evolving towards structural homogeneity; and China and the US lead most countries in many common areas. China has the potential to overtake the US in competitiveness in the future. We suggest that China increase its competitiveness by promoting its advantages, addressing its weaknesses and focusing on core areas. 展开更多
关键词 national competitiveness comparison between China and the US factor eterogeneity
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Synthesis of Citrinin Artificial Antigen and Its Coupling Ratio Determination 被引量:3
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作者 李娇 钟理 +5 位作者 田世民 金涌 崔艳芬 任香夫 祁淑红 刘畅 《Agricultural Science & Technology》 CAS 2010年第8期169-172,共4页
[Objective] This study was to establish a method for the rapid and accurate detection of the coupling ratio of artificial antigen. [Method] Artificial synthetic antigen of citrinin (CIT) was first conjugated with ve... [Objective] This study was to establish a method for the rapid and accurate detection of the coupling ratio of artificial antigen. [Method] Artificial synthetic antigen of citrinin (CIT) was first conjugated with vector protein bovine serum albumin (BSA) and then identified by SDS-PAGE electrophoresis,and its coupling ratio was measured by UV absorption and mass spectrometry. [Result] The identification result showed that artificial antigen of CIT was successfully coupled,and the coupling ratio was 8.4 by UV absorption while 6.0 by mass spectrometry. [Conclusion] The comparison experiment showed that mass spectrometry could rapidly identify the artificial antigen and accurately detect its coupling ratio. This study provided basis for the preparation of CIT antigen as well as the establishment of an for enzyme-linked immunosorbent assay (ELISA) for citrinin determination. 展开更多
关键词 CITRININ Artificial antigen Coupling ratio Mass spectrometry
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要以积极的心态同成功者比
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作者 张殿君 辛举 宋科暖 《莱阳农学院学报(社会科学版)》 2004年第1期47-51,共5页
与成功者相比 ,有积极和消极两种心态之分。以积极的心态与成功者相比 ,就是比起点 ,树立信心 ;比素质 ,提高自我 ;比付出 。
关键词 积极心态 比起点 比素质 比付出
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Analysis and Optimum Design of Differential Inductors Using Distributed Capacitance Model
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作者 菅洪彦 唐长文 +1 位作者 何捷 闵昊 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2005年第6期1077-1082,共6页
A distributed capacitance model for monolithic inductors is developed to predict the equivalently parasitical capacitances of the inductor.The ratio of the self-resonant frequency (f SR) of the differential-driven sym... A distributed capacitance model for monolithic inductors is developed to predict the equivalently parasitical capacitances of the inductor.The ratio of the self-resonant frequency (f SR) of the differential-driven symmetric inductor to the f SR of the single-ended driven inductor is firstly predicted and explained.Compared with a single-ended configuration,experimental data demonstrate that the differential inductor offers a 127% greater maximum quality factor and a broader range of operating frequencies.Two differential inductors with low parasitical capacitance are developed and validated. 展开更多
关键词 distributed capacitance model self-resonant frequency ratio quality factor differential inductor optimum design
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RELATIONSHIPS OF STARCH CONCENTRATION WITH SPECIFIC LEAF WEIGHT AND MINERAL CONCENTRATIONS IN POTATO LEAVES UNDER VARIED CO_2 AND TEMPERATURE 被引量:2
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作者 曹卫星 Theodore W.Tibbitts 《Acta Botanica Sinica》 CSCD 1997年第12期1118-1125,共8页
Foliar concentrations of starch and major nutrients N, P, K, Ca, and Mg along with specific leaf weight (SLW) were determined in the potato (Solanun tuberosum L.) cvs "Denali", "Norland "'and &... Foliar concentrations of starch and major nutrients N, P, K, Ca, and Mg along with specific leaf weight (SLW) were determined in the potato (Solanun tuberosum L.) cvs "Denali", "Norland "'and "Russet Burbank" grown for 35 days under the CO2 concentrations of 500, 1 000, 1 500 and 2 000 mol mol-1 at both 16 and 20℃ air temperature. The starch concentration, pooled from the three cultivars, increased with increasing CO2 concentration at both 16 and 20℃,, and was consistently higher at 16℃ than at 20℃. The SLW (g m-2) was positively related to the foliar starch concentration on the basis of leaf area or dry weight. The concentrations of N, P, Ca, and Mg in leaves were negatively related to starch concentration under 14% starch on a dry weight basis. Above 14%, there was no significant relationship between nutrient and starch concentrations . The similar patterns were seen when the SLW and nutrient concentrations were expressed on a starch-free basis. In contrast, the leaf concentration of K was not closely related to the starch concentration. The results indicated that the changes in SLW and concentrations of N, P, Ca, and Mg in potato leaves only partially resulted from the changed starch concentration. 展开更多
关键词 CO_2 concentration Temperature Specific leaf weight Starch concentration Mineral concentration POTATOES
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An online method to determine chlorine stable isotope composition by continuous flow isotope ratio mass spectrometry (CF-IRMS) coupled with a Gasbench Ⅱ 被引量:3
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作者 刘运德 周爱国 +3 位作者 甘义群 刘存富 余婷婷 李小倩 《Journal of Central South University》 SCIE EI CAS 2013年第1期193-198,共6页
An online method using continuous flow isotope ratio mass spectrometry (CF-IRMS) interfaced with a Gasbench Ⅱ was presented to determine chlorine stable isotope composition. Silver chloride (AgCl) was quantitativ... An online method using continuous flow isotope ratio mass spectrometry (CF-IRMS) interfaced with a Gasbench Ⅱ was presented to determine chlorine stable isotope composition. Silver chloride (AgCl) was quantitatively derived from chloride by using silver nitrate (AgNO3), and then was reacted with iodomethane (CH3Ⅰ) to produce methyl chloride (CH3Cl). A GasBench Ⅱ equipped with a PoraPlot Q column was used to separate CH3Cl from any other gas species. Finally, chlorine stable isotope analysis was carried out on CH3Cl introduced to the IRMS in a helium stream via an active open split. The minimum amount of Cl used in this method is of the order of 1.4 μmol. Inter-laboratory and inter-technique comparisons show that the total uncertainty incorporating both the precision and accuracy of this method is better than 0.007%. Furthermore, ten seawaters sampled from different locations have a narrow δ37Cl value range from -0.008% to 0.010%, with a mean value of (0.000±0.006)%. This supports the assumption that any seawater can be representative of standard mean ocean chloride (SMOC) and used as an international reference material. 展开更多
关键词 chlorine stable isotope continuous flow isotope ratio mass spectrometry CF-IRMS GasBench
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Formation and Characteristics of Acrylonitrile/Urea Inclusion Compound
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作者 邹均庭 王雨松 +2 位作者 庞文民 石磊 鲁非 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2013年第2期198-202,I0004,共6页
The formation process and composition of the acrylonitrile/urea inclusion compounds (AN/UIC) with different aging times and AN/urea molar feed ratios are studied by differential scanning calorimetry (DSC) and X-ra... The formation process and composition of the acrylonitrile/urea inclusion compounds (AN/UIC) with different aging times and AN/urea molar feed ratios are studied by differential scanning calorimetry (DSC) and X-ray diffraction (XRD). It is suggested that DSC can determine the guest/host ratio and the heat of decomposition. Meanwhile, the guest/host ratio and heat of decomposition are obtained, which are 1.17 and 5361.53 J/mol, respec- tively. It is suggested AN molecules included in urea canal lattice may be packed flat against each other. It is found that the formation of AN/UIC depends on the aging time. XRD results reveal that once AN molecules enter urea lattice, AN/UIC are formed, which possess the final structure. When AN molecules are sufficient, the length of AN molecular arrays in urea canals increases as aging time prolonging until urea tunnels are saturated by AN. 展开更多
关键词 ACRYLONITRILE Urea inclusion compound Molar ratio Heat of decomposition Formation process
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Determination of Hf–Sr–Nd isotopic ratios by MC-ICP-MS using rapid acid digestion after flux-free fusion in geological materials 被引量:4
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作者 Zhian Bao Chunlei Zong +3 位作者 Linru Fang Honglin Yuan Kaiyun Chen Mengning Dai 《Acta Geochimica》 EI CAS CSCD 2018年第2期244-256,共13页
In this study, we established a rapid acid digestion for determining Hf-Sr-Nd isotopic ratios of geological samples by using MC-ICP-MS. Conditions of 1600 ℃ for 1 min and 1400 ℃ for 1 min were adopted for fusing int... In this study, we established a rapid acid digestion for determining Hf-Sr-Nd isotopic ratios of geological samples by using MC-ICP-MS. Conditions of 1600 ℃ for 1 min and 1400 ℃ for 1 min were adopted for fusing intrusive rocks and extrusive rocks, respectively. The rapid acid digestion technique is superior in digestion time compared with high-pressure PTFE bomb method. The procedural blanks of the method were also lower than that flux fusion. Replicate analyses of international certified reference materials (CRMs) indicate that isotopic ratios of ^176Hf/^177Hf, ^87Sr/^86Sr and 143Nd/144Nd agree well with previously published data. The external reproducibility (2SD, n = 5) of ten CRMs are ±0.000030 for ^87Sr/^86Sr, ± 0.000030 for ^143Nd/^144Nd, and ±0.000018 for ^176Hf/^177Hf. 展开更多
关键词 Certified reference material Flux-free fusion Hf-Sr-Nd isotopic ratio Procedural blank Rapid acid digestion
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Ratios of Closely Related Elements in Soil and Their Implications 被引量:1
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作者 XINGGUANG-XI HOUWEN-HUA 《Pedosphere》 SCIE CAS CSCD 1991年第4期333-343,共11页
This paper has investigated the ratios of closely related elements such as Mn,Cr,V,Ni,Co,Cu,Pb,Cd,Ba,Sr,La and Ce in the major soils of China,and the factors affecting them,and explored their use as indicators in soil... This paper has investigated the ratios of closely related elements such as Mn,Cr,V,Ni,Co,Cu,Pb,Cd,Ba,Sr,La and Ce in the major soils of China,and the factors affecting them,and explored their use as indicators in soil formation,material transport and environmental pollution.Results show that the effect of soil-forming processes on the ratios of closely related elements varied with different elements,and became greater in the sequence of Ce/La <V/Cr≈Ni/Co<Zn/Cu≈Zn/Pb<Zn/Cd<Mn/Cr<Ba/Sr.The magnitude of the variation in the ratios of closely related elements depended on the chemical properties of the elements themselves,on the one hand,and the parent material and climatic conditions on the other.The ratio of Ba/Sr showed a distinct zonality,decreasing gradually in the sequence:cool temperate zone acid soils>grassland soils>desert soils and increasing gradually from the semi-arid subhumid zone soils>the temperate zone neutral soils>the north subtropic zone soils>tropical and subtropical acid soils. 展开更多
关键词 abundance of elements material transport ratios of closely related elements soil-forming processes
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Accurate and precise determination of lead isotope composition in selected geochemical reference materials 被引量:2
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作者 Guangliang Wu Jian-Ming Zhu +3 位作者 Decan Tan Guilin Han Lixing Zhang Kun Ren 《Acta Geochimica》 EI CAS CSCD 2017年第3期421-425,共5页
Lead(Pb)isotopes have been extensively employed in tracing sources of Pb and its transport pathways through the environment.However,Pb isotopic ratios in related geochemical reference materials are scarce.Here,we repo... Lead(Pb)isotopes have been extensively employed in tracing sources of Pb and its transport pathways through the environment.However,Pb isotopic ratios in related geochemical reference materials are scarce.Here,we report high-precision Pb isotopic ratios measured by Nu Plasma II MC-ICP-MS using calibrated ^(205)Tl/^(203)Tl=2.38865(NIST SRM 997)for mass discrimination correction.The long-term external precision(2SD)for NISTSRM 981 of Pb,BCR-2,and BHVO-2 are 0.31‰(n=105),0.42‰(n=11),and 0.25‰(n=5)for ^(208)Pb/ ^(206)Pb and 0.16‰,0.53‰,and 0.07‰for ^(206)Pb/ ^(207)Pb,both respectively,and their Pb isotopic ratios are in excellent agreement with the recommended values.Using this method,we report for the first time Pb isotopic compositions in shale SGR-1b(USGS);coal CLB-1(USGS);stream sediments GSD-17,-21,and-23(IGGE);soils GSS-12,-13,-14,-15,and-16(IGGE);plants GSV-1,-2,and-3(IGGE);and human hair GSH-1(IGGE). 展开更多
关键词 Lead isotopes Geochemical reference materials MC-ICP-MS
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Meta-Analysis of Trials Comparing Gemcitabine and Pegylated Liposomal Doxorubicin for Treatment in Women with Progressive or Recurrent Ovarian Cancer
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作者 Xia Liu Li Ma +1 位作者 Jinhui Tian Kehu Yang 《Clinical oncology and cancer researeh》 CAS CSCD 2009年第6期412-417,共6页
OBJECTIVE To evaluate the efficacy and adverse effects ofgemcitabine versus pegylated liposomal doxorubicin in patientswith progressive or recurrent ovarian cancer.METHODS We conducted a systematic literature search t... OBJECTIVE To evaluate the efficacy and adverse effects ofgemcitabine versus pegylated liposomal doxorubicin in patientswith progressive or recurrent ovarian cancer.METHODS We conducted a systematic literature search toidentify all randomized controlled trials comparing gemcitabineand pegylated liposomal doxorubicin for progressive orrecurrent ovarian cancer. Trial data were reviewed and extractedindependently by 2 reviewers. We evaluated the quality of theincluded studies using the Handbook 5.0 recommend standardsand then analyzed data by Cochrane Collaboration's RevMan 5.0.RESULTS Two trials which included a total of 348 patients wereanalyzed. The results of meta-analysis showed that gemcitabineimproved disease control rates significantly better than pegylatedliposomal doxorubicin. A greater number of patients receivinggemcitabine experienced neutropenia compared with patientsreceiving pegylated liposomal doxorubicin; however, hand-footsyndrome and mucositis were more severe in patients receivingpegylated liposomal doxorubicin.CONCLUSION Gemcitabine provided a limited advantagecompared with pegylated liposomal doxorubicin. There existsan urgent need for more high-quality, multicenter, adequaterandomized, controlled clinical trials for comparing gemcitabinewith pegylated liposomal doxorubicin in patients withprogressive/recurrent ovarian cancer. 展开更多
关键词 GEMCITABINE pegylated liposomal doxorubicin ovarian cancer meta-analysis.
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加强文化素质培养 造就跨世纪人才
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作者 石亚军 《教学与研究》 CSSCI 北大核心 1995年第6期66-67,共2页
加强文化素质培养 造就跨世纪人才石亚军加强对大学生进行文化素质的培养.是适应市场经济发展的新形势,培养跨世纪人才的客观要求。对文科院校来说,则显得尤为重要、我们中国人民大学是一所以人文科学、社会科学和管理科学为主、文... 加强文化素质培养 造就跨世纪人才石亚军加强对大学生进行文化素质的培养.是适应市场经济发展的新形势,培养跨世纪人才的客观要求。对文科院校来说,则显得尤为重要、我们中国人民大学是一所以人文科学、社会科学和管理科学为主、文理兼容的综合性大学。近几年来。在面... 展开更多
关键词 素质培养 加强文化 跨世纪人才 大学生 文化素质 通识教育 比素质 教学计划 课程建设 建设有中国特色的社会主义理论
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大批优秀企业家涌现之时就是中国经济兴旺之日 被引量:1
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作者 齐向武 《中国企业家》 1996年第8期7-8,共2页
随着我国改革开放的不断发展,企业家的地位和作用越来越重要,对企业家的要求也越来越高。因此,加强企业家素质修养,提高工作能力,充分体现了党和人民的信任和委托,既是改革开放的迎接跨世纪的迫切要求,也是社会主义企业家队伍的内在需要... 随着我国改革开放的不断发展,企业家的地位和作用越来越重要,对企业家的要求也越来越高。因此,加强企业家素质修养,提高工作能力,充分体现了党和人民的信任和委托,既是改革开放的迎接跨世纪的迫切要求,也是社会主义企业家队伍的内在需要。 当前国际上企业界有三大名言: 智力比知识更重要。知识再丰富、智力不足,运用知识的能力很差,知识也不能很好发挥作用。 素质比智力更重要。知识丰富,智力发达,如果素质欠佳也不行。 觉悟比素质更重要。 展开更多
关键词 优秀企业家 企业家队伍 中国经济 社会主义企业家 智力不足 果素 智力发达 比素质 企业界 经理人员
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Strontium isotope analysis of archaeological fauna at the Erlitou site 被引量:2
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作者 ZHAO ChunYan YANG Jie +4 位作者 YUAN Jing LI ZhiPeng XU Hong ZHAO HaiTao CHEN GuoLiang 《Science China Earth Sciences》 SCIE EI CAS 2012年第8期1255-1259,共5页
The Erlitou site is located at Yanshi City,Henan Province.This site is a large settlement site of Erlitou culture,and it is dated to 3800-3500 a BP.Five kinds of domestic animals,i.e.,dogs,pigs,sheep,goats,and cattle ... The Erlitou site is located at Yanshi City,Henan Province.This site is a large settlement site of Erlitou culture,and it is dated to 3800-3500 a BP.Five kinds of domestic animals,i.e.,dogs,pigs,sheep,goats,and cattle were found from the site.In this paper,two problems have emerged in studies involving the estimation of local isotope levels and the distinction of migrants from locals.Tooth enamel samples from 17 domestic animals individuals were analyzed for strontium isotope ratio(87Sr/86Sr),by the thermal ionization mass spectrometry,including 10 pigs,5 sheep and 2 cattle.The results show that the mean 87Sr/86Sr ratios of 10 pigs enamel samples were 0.712078,Based on the local strontium isotopes ratio range determined by the mean 87Sr/86Sr ratios ±2 of 10 pig enamel samples(0.712256-0.711900),we found that five sheep and one cattle from the Erlitou site fell well outside the local strontium isotopes ratio range and were considered to be non-local. 展开更多
关键词 Erlitou site FAUNA strontium isotopes
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