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复杂地质情况下的分类型合成地震记录标定技术——以孤南209井区为例 被引量:1
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作者 李海涛 钮学民 孟宪军 《油气地球物理》 2005年第3期42-44,共3页
高精度合成地震记录标定是精细储层描述的基础。复杂地质条件下,地震资料也复杂,常规的合成记录标定不能达到准确标定的目的。实践表明,复杂地质区块的合成记录标定特别需要做好以下几个方面的工作:①地震资料反射特征分析;②提取符合... 高精度合成地震记录标定是精细储层描述的基础。复杂地质条件下,地震资料也复杂,常规的合成记录标定不能达到准确标定的目的。实践表明,复杂地质区块的合成记录标定特别需要做好以下几个方面的工作:①地震资料反射特征分析;②提取符合工区地质特征的空变子波;③按不同地震反射特征分类型进行单井标定;④在研究工区地质规律的基础上进行合理的横向多井联合标定(调整)。本文以孤南209井区为例,介绍在复杂地质情况下分类型合成记录标定的效果。 展开更多
关键词 类型合成地震记录标定技术 地质条件 地震资料 反射特征 空变子波 单井标定
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微波辐射下N-取代乙酰胺的合成
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作者 李艳秋 王玉炉 王瑾晔 《河南师范大学学报(自然科学版)》 CAS CSCD 北大核心 2007年第3期88-90,共3页
报道了一种简单有效的合成N-取代乙酰胺的新方法.在微波辐射、无溶剂条件下,1.5摩尔比率的乙酸酐和一系列胺发生反应合成15个N-取代乙酰胺,该方法操作简便,反应时间短,产率高.更重要的是该方法适用范围较广(脂肪胺、芳香胺、杂环胺).环... 报道了一种简单有效的合成N-取代乙酰胺的新方法.在微波辐射、无溶剂条件下,1.5摩尔比率的乙酸酐和一系列胺发生反应合成15个N-取代乙酰胺,该方法操作简便,反应时间短,产率高.更重要的是该方法适用范围较广(脂肪胺、芳香胺、杂环胺).环境友好. 展开更多
关键词 微波 无溶剂 N-取代乙酰胺 合成类型
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汉语三字格习语概念合成的认知考察
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作者 黄龙 余玲丽 姜玲 《现代语文(下旬.语言研究)》 2013年第7期27-30,共4页
汉语中存在许多三字格习语。本文以概念合成理论为视角,探讨汉语三字格习语的合成类型和内在认知机制。我们认为,从概念合成的层级性角度看,三字格习语的合成分为高层级合成和中层级合成;从合成方式的不同看,又可将其分为自然组合性合... 汉语中存在许多三字格习语。本文以概念合成理论为视角,探讨汉语三字格习语的合成类型和内在认知机制。我们认为,从概念合成的层级性角度看,三字格习语的合成分为高层级合成和中层级合成;从合成方式的不同看,又可将其分为自然组合性合成、糅合型和截搭型三种合成类型,且三字格习语大多属于糅合型合成,在糅合型概念合成中会出现先截搭后糅合或者先自然组合后糅合的构成方式。 展开更多
关键词 三字格习语概念合成理论认知机制合成类型
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分析DOX抗癌药物前药的合成及表征
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作者 姜兵兵 曾银海 《饮食科学》 2018年第11X期158-158,共1页
DOX抗癌药物的合理应用是关键,前药的合成和表征等存在差异,合成PH值有一定敏感性,如何充分利用丁二酸桥接,合成了非PH敏感前药PEG-DOX,采用核磁共氢谱对所有合成药物的表征分析,确定实际药量。考察分析两种前药的药物释放行为,结果表明... DOX抗癌药物的合理应用是关键,前药的合成和表征等存在差异,合成PH值有一定敏感性,如何充分利用丁二酸桥接,合成了非PH敏感前药PEG-DOX,采用核磁共氢谱对所有合成药物的表征分析,确定实际药量。考察分析两种前药的药物释放行为,结果表明,成功的合成药物,确定药物剂量高,根据研究要求可知,产率高,直接应用在药物合成中,希望能够为广大同行提供一定的参考作用。 展开更多
关键词 DOX抗癌药物 合成类型 表征形式
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The occurrence,fate,and distribution of natural and synthetic hormones in different types of wastewater treatment plants in Iran 被引量:1
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作者 Mohammad Mehdi Amin Bijan Bina +3 位作者 Afshin Ebrahimi Zeynab Yavari Farzaneh Mohammadi Somayeh Rahimi 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2018年第5期1132-1139,共8页
Over the past few years, the presence of steroid estrogens in the environment has become a major concern. In this study, the concentrations of estrone (El), 17β-estradinl (E2), and 17α-ethinyl estradiol (EE2) ... Over the past few years, the presence of steroid estrogens in the environment has become a major concern. In this study, the concentrations of estrone (El), 17β-estradinl (E2), and 17α-ethinyl estradiol (EE2) were measured in some wastewater treatment plants (WWTPs) in lran. These samples were collected from the municipal, rural, livestock, commercial, and hospital WWTPs, extracted by dispersive liquid-liquid micro extraction (DLLME) technique, derivatized, and detected by GC/MS. In these treatment plants, various processes including conven- tional activated sludge (CAS), aerated lagoon (AL), moving bed biofilm reactor (MBBR), and activated sludge with wetland (AS + WL) are used. The highest concentration of hormones was observed in the influents and effluents of livestock, municipal, commercial, and hospital WWTPs, respectively. The maximum elimination rate was obtained in MBBR followed by AS + WL CAS and AL The biodegradation and adsorption rates along with adsorption coefficients of 1g kd and 1g koc were measured for all target compounds. 展开更多
关键词 INFLUENT EFFLUENT ESTROGEN Wastewater BIODEGRADATION
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Herbal compound 861 regulates mRNA expression of collagen synthesis- and degradation-related genes in human hepatic stellate cells 被引量:6
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作者 Lin Wang Jlan Wang +2 位作者 Xue-Hai Tan Bao-En Wang Pei-Gen Xiao 《World Journal of Gastroenterology》 SCIE CAS CSCD 2008年第11期1790-1794,共5页
AIM: To identify the role of herbal compound 861 (Cpd 861) in the regulation of mRNA expression of collagen synthesis- and degradation-related genes in human hepatic stellate cells (HSCs). METHODS: mRNA levels o... AIM: To identify the role of herbal compound 861 (Cpd 861) in the regulation of mRNA expression of collagen synthesis- and degradation-related genes in human hepatic stellate cells (HSCs). METHODS: mRNA levels of collagen types I and III, matrix metalloproteinase 1 (MMP-1), matrix metalloproteinase 2 (MMP-2), membrane type-1 matrix metalloproteinase (MT1-MMP), tissue inhibitor of metalloproteinase 1 (TIMP-1), and transforming growth factor β1 (TGF-β1) in cultured-activated HSCs treated with Cpd 861 or interferon-γ, (IFN-γ,) were determined by real-time PCR. RESULTS: Both Cpd 861 and IFN-γ reduced the mRNA levels of collagen type Ⅲ, MMP-2 and TGF-β1. Moreover, Cpd 861 significantly enhanced the MMP-1 mRNA levels while down-regulated the TIMP-1 mRNA expression, increasing the ratio of MMP-1 to TIMP-1 to (6.3 + 0.3)- fold compared to the control group. CONCLUSION: The anti-fibrosis function of Cpd 861 may be mediated by both decreased interstitial collagen sythesis by inhibiting the transcription of collagen type Ⅲ and TGF-β1 and increased degradation of these collagens by up-regulating MMP-1 and down-regulating TIMP-1 mRNA levels. 展开更多
关键词 Herbal Compound 861 Human hepatic stellate cells Collagen synthesis and degration Collagen type Matrix metalloproteinase 1 Tissue inhibitor of metalloproteinase 1
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Brain MRI Segmentation Using KFCM and Chan-Vese Model 被引量:1
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作者 吴一全 侯雯 吴诗婳 《Transactions of Tianjin University》 EI CAS 2011年第3期215-219,共5页
To extract region of interests (ROI) in brain magnetic resonance imaging (MRI) with more than two objects and improve the segmentation accuracy, a hybrid model of a kemel-based fuzzy c-means (KFCM) clustering al... To extract region of interests (ROI) in brain magnetic resonance imaging (MRI) with more than two objects and improve the segmentation accuracy, a hybrid model of a kemel-based fuzzy c-means (KFCM) clustering algorithm and Chan-Vese (CV) model for brain MRI segmentation is proposed. The approach consists of two succes- sive stages. Firstly, the KFCM is used to make a coarse segmentation, which achieves the automatic selection of initial contour. Then an improved CV model is utilized to subdivide the image. Fuzzy membership degree from KFCM clus- tering is incorporated into the fidelity term of the 2-phase piecewise constant CV model to obtain accurate multi-object segmentation. Experimental results show that the proposed model has advantages both in accuracy and in robustness to noise in comparison with fuzzy c-means (FCM) clustering, KFCM, and the hybrid model of FCM and CV on brain MRI segmentation. 展开更多
关键词 brain magnetic resonance imaging image segmentation kernel-based fuzzy c-means clustering ChanVese model
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A STUDY ON RELATION BETWEEN EAST ASIAN WINTER MONSOON AND CLIMATE CHANGE DURING RAINING SEASON IN CHINA
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作者 晏红明 段玮 肖子牛 《Journal of Tropical Meteorology》 SCIE 2004年第1期23-33,共11页
Based on the data of NCEP, OLR and rainfall of China, we studied the influences of the East Asian winter monsoon activities on the precipitation during the raining season over China by correlation analysis and composi... Based on the data of NCEP, OLR and rainfall of China, we studied the influences of the East Asian winter monsoon activities on the precipitation during the raining season over China by correlation analysis and composite analysis. The result shows that annual and interdecadal change of East Asian winter monsoon is distinct. It is strong from 1950s to the middle of 1980s but weak after the middle of 1980s. The effect of abnormal winter monsoon on the precipitation during raining season is significant over the middle and lower reaches of the Changjiang River basin. It is revealed that the precipitation will increase when preceding winter monsoon is weak but decrease when preceding winter monsoon is strong. In this paper, some appropriate reasons are given to explain the abnormal rainfall by analyzing the distribution of SSTA and the variation of summer circulation. It is pointed out definitely that the variation of SSTA and summer circulation is a primary cause for abnormal rainfall over the middle and lower reaches of the Changjiang River. 展开更多
关键词 East Asian winter monsoon East Asian subtropical summer monsoon summer precipitation over the middle and lower reaches area of the Changjiang River
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Relationships between high-molecular-weight glutenin subunit (HMW-GS), pentosan and various component contents in different wheat varieties
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作者 LI Chun-xi ZHANG Bei-bei SHAO Yun JIANG Li-na LI Dan-dan 《Journal of Life Sciences》 2007年第1期22-29,33,共9页
The composition of HMW-GS and pentosan and its various component contents in different wheat varieties were analyzed. According to scores of these subunits in several wheat varieties, the correlation relationship betw... The composition of HMW-GS and pentosan and its various component contents in different wheat varieties were analyzed. According to scores of these subunits in several wheat varieties, the correlation relationship between the composition of HMW-GS, subunit combination types and pentosan, various components and component ratio were ascertained. The results showed that HMW-GSs were very diverse which had 11 types. In different varieties, the variation of Ara was obvious while Xyl was not; pentosan and its various component contents were very different, and their coefficient of variability was quite high. The majority of parameters had a significant negative correlation with Glu-1 where Glu-D1 was stronger than other two loci. N, 7, 17+18 and 2+12 subunits had influence on pentosan and its various component contents. But some subunits such as 1 and 5+ 10 which are good for baking quality had little contribution to pentosan and various component contents. The pentosan and various component contents were higher in the varieties which had (N, 7, 2+12) subunit combinations. Additionally, the 21 varieties were classified into 4 categories according to HMW-GS scores and pentosan content. 展开更多
关键词 WHEAT HMW-GS PENTOSAN correlation classification
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基于席夫碱反应的共价有机骨架材料 被引量:7
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作者 张成江 袁晓艳 +3 位作者 袁泽利 钟永科 张卓旻 李攻科 《化学进展》 SCIE CAS CSCD 北大核心 2018年第4期365-382,共18页
席夫碱共价有机骨架材料(Schiff-base COFs)是根据Schiff-base反应原理缩合形成的一类COFs材料。Schiff-base COFs具有骨架密度低、比表面积大、孔径尺寸可控、有机单体种类丰富、合成方法灵活多样、表面化学性质可功能化,易于引入特定... 席夫碱共价有机骨架材料(Schiff-base COFs)是根据Schiff-base反应原理缩合形成的一类COFs材料。Schiff-base COFs具有骨架密度低、比表面积大、孔径尺寸可控、有机单体种类丰富、合成方法灵活多样、表面化学性质可功能化,易于引入特定的分子识别位点,以及物理化学稳定性优异等特征。Schiff-base COFs在气体吸附/储存、传感、催化、光电材料和前处理介质等诸多领域有重要的应用前景,成为材料科学领域的研究热点。本文主要综述了近年来Schiff-base COFs材料的合成类型、制备方法,以及该材料在不同领域的应用研究进展。最后,总结了该材料的研究现状并展望了该研究领域未来的发展方向和应用前景。 展开更多
关键词 席夫碱反应 共价有机骨架 合成类型 制备方法 应用研究
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Displacement manifold method for type synthesis of lower-mobility parallel mechanisms 被引量:28
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作者 LI Qinchuan HUANG Zhen Jacques Marie Hervé 《Science China(Technological Sciences)》 SCIE EI CAS 2004年第6期641-650,共10页
Type synthesis of lower-mobility parallel mechanisms is a hot and frontier topic in international academic and industrial field. Based on the Lie group theory, a displacement manifold synthesis method is proposed. For... Type synthesis of lower-mobility parallel mechanisms is a hot and frontier topic in international academic and industrial field. Based on the Lie group theory, a displacement manifold synthesis method is proposed. For all the nine kinds of lower-mobility parallel mechanisms, the mechanism displacement manifold, limb displacement manifold and the geometrical conditions which guarantee that the intersection of the limb displacement manifold is the desired mechanism displacement manifold are enumerated. Various limb kinematic chains can be obtained using the product closure of displacement subgroup. Parallel mechanisms can be constructed with these limbs while obeying the geometrical conditions. Hence, all the nine kinds of lower-mobility parallel mechanisms can be synthesized using this method. Since displacement manifold deals with finite motion, the result mechanism of synthesis have full-cycle mobility. Novel architectures of lower-mobility parallel mechanisms can be obtained using this method. 展开更多
关键词 lower-mobility parallel mechanisms Lie group displacement manifold type synthesis
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Chemical synthesis of a cyclotide via intramolecular cyclization of peptide O-esters 被引量:5
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作者 ZHENG Ji-Shen CHANG Hao-Nan +1 位作者 SHI Jing LIU Lei 《Science China Chemistry》 SCIE EI CAS 2012年第1期64-69,共6页
Cyclotides constitute a fascinating family of circular proteins containing ca.30 amino acid residues.They have a unique cyclic cysteine knot topology and exhibit remarkable thermal,chemical and enzymatic stabilities.T... Cyclotides constitute a fascinating family of circular proteins containing ca.30 amino acid residues.They have a unique cyclic cysteine knot topology and exhibit remarkable thermal,chemical and enzymatic stabilities.These characteristics enable them to have a range of biological activities and promising pharmaceutical and agricultural applications.Here,we present a practical strategy for the chemical synthesis of cyclotides through the intramolecular ligation of fully unprotected peptide O-esters.This strategy involves the mild Fmoc solid-phase peptide synthesis of the peptide O-ester backbone,the head-to-tail cyclization of the cyclotide backbone by native chemical ligation,and the oxidative refolding to yield the natural knot protein.The simplicity and high efficiency of the strategy can be employed in the synthesis of artificial cyclotides for pharmaceutical applications. 展开更多
关键词 CYCLOTIDES chemical synthesis peptide O-ester native chemical ligation MACROLACTAMIZATION
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Diagnosing holographic type dark energy models with the Statefinder hierarchy, composite null diagnostic and w-w′pair
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作者 Ze Zhao Shuang Wang 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS CSCD 2018年第3期65-76,共12页
The main purpose of this work is to distinguish various holographic type dark energy (DE) models, including the AHDE, HDE, NADE, and RDE model, by using various diagnostic tools. The first diagnostic tool is the Sta... The main purpose of this work is to distinguish various holographic type dark energy (DE) models, including the AHDE, HDE, NADE, and RDE model, by using various diagnostic tools. The first diagnostic tool is the Statefinder hierarchy, in which the evolution of Statefinder hierarchy parmeter S3(1)(z) and S4(1)(z) are studied. The second is composite null diagnostic (CND), in which the trajectories of {S(1)4, ∈} and {S4(1), e} are investigated, where ∈ is the fractional growth parameter. The last is w-w′ analysis, where w is the equation of state for DE and the prime denotes derivative with respect to lna. In the analysis we consider two cases: varying current fractional DE density Ωde0 and varying DE model parameter C. We find that: (1) both the Statefinder S4(1) can lead to larger hierarchy and the CND have qualitative impact on AHDE, but only have quantitative impact on HDE. (2) S4(1) differences than S 4(1), while the CND pair has a stronger ability to distinguish different models than the Statefinder hierarchy. (3) For the case of varying C, the {w, w′} pair has qualitative impact on AHDE; for the case of varying Ωde0, the {w, w′} pair only has quantitative impact; these results are different from the cases of HDE, RDE, and NADE, in which the {w, w′} pair only has quantitative impact on these models. In conclusion, compared with HDE, RDE, and NADE, the AHDE model can be easily distinguished by using these diagnostic tools. 展开更多
关键词 dark energy COSMOLOGY cosmological constant
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Synthesis,structure and bonding of the hypoelectronic cluster compound Sr_3Tl_5
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作者 LI DongXu LUO GengGeng +1 位作者 XIAO ZiJing DAI JingCao 《Science China Chemistry》 SCIE EI CAS 2012年第1期131-137,共7页
The Sr3Tl5 phase was prepared by high temperature synthesis techniques through reaction of the high purity elements in the welded Nb tubes.The structure established through X-ray structural analysis shows the compound... The Sr3Tl5 phase was prepared by high temperature synthesis techniques through reaction of the high purity elements in the welded Nb tubes.The structure established through X-ray structural analysis shows the compound is a good hypoelectronic trielide example of the Pu3Pd5 structural type in which skeletal electron count is lower than in a traditional Zintl phase(Cmcm,Z = 4;a = 10.604(2) ,b = 8.675(2) ,and c = 10.985(2) ;V = 1010.5(3) 3).The strontium size and the compound's polarity appear responsible for this thallium phase crystallization in the Pu3Pd5 family type rather than the isoelectronic Sr3In5 version.A first-principle electronic structure calculation(LMTO) demonstrates that the strontium atoms participate substantially in Sr-Tl bonding in the structure. 展开更多
关键词 Zintl phases hypoelectronic cluster polar intermetallics LMTO calculations
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Racemic X-ray structure of L-type calcium channel antagonist Calciseptine prepared by total chemical synthesis 被引量:3
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作者 Chen-Chen Chen Shuai Gao +3 位作者 Hua-Song Ai Qian Qu Chang-Lin Tian Yi-Ming Li 《Science China Chemistry》 SCIE EI CAS CSCD 2018年第6期702-707,共6页
Snake toxin Calciseptine as a natural antagonist of L-type calcium channel has potential drug values, but its structural information remains unknown. Here, we report the total chemical synthesis of Calciseptine by usi... Snake toxin Calciseptine as a natural antagonist of L-type calcium channel has potential drug values, but its structural information remains unknown. Here, we report the total chemical synthesis of Calciseptine by using hydrazide based native chemical ligation. The crystal structure of Calciseptine was determined by racemic protein crystallography technique. Compared to the structure of its homologous family protein, we found that Calciseptine is adopting a typical three-finger structure. 展开更多
关键词 protein chemical synthesis calciseptine hydrazide based native chemical ligation racemic protein crystallography
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