检索结果-南通市图书馆

Communications in Theoretical Physics 2006年第2X期46卷 193-198页

作者： li de-Sheng LUO Cheng-Xin College of Mathematics and Systems Science Shenyang Normal University Shenyang 110034 China

In this paper, we improve the method for deriving Jacobi elliptic function solutions of nonlinear evolution equations given in Ref. [12] and apply it to the integrable higher-order Broer-Kaup system in （2＋1）-dimens... 详细信息

关键词： Jacobi elliptic function projective Riccati equation higher-order Broer-Kaup system exact solutions

The trade margins of Chinese agricultural exports to ASEAN and their determinants

在线全文

学校读者我要写书评

暂无评论

Journal of Integrative Agriculture 2018年第10期17卷 2356-2367页

作者： SUN Zhi-lu li Xian-de Institute of Agricultural Economics and development Chinese Academy of Agricultural Sciences

How do Chinese agricultural exports to ASEAN（Association of Southeast Asian Nations） evolve？ And what factors affected the evolution pattern？ This study measures the trade margins of Chinese agricultural exports to ASEAN by utilizing the 2000-2015 Harmonized System＇s six-digit agricultural trade data, and further analyzes their determinants by developing an augmented gravity model of international trade. The results indicate that, the main growth source of Chinese agricultural exports to ASEAN has shifted from the extensive margin before the formal establishment of CAFTA（China-ASEAN Free Trade Area） in 2010 to the intensive margin since the formal establishment of CAFTA, but changes in Chinese agricultural exports to ASEAN have always mainly depended on the intensive margin. Since the formal establishment of CAFTA, the evolution pattern of Chinese agricultural exports to ASEAN has shifted from ＂more varieties, low price, and small quantity＂ to ＂less varieties, high price, and large quantity＂. Relative economic scale, relative population scale, capacity of agricultural export, trade integration, global financial crisis, and common border significantly affect the trade margins of Chinese agricultural exports to ASEAN.

关键词： China agricultural product ASEAN trade margins

冀鲁豫边区红色文化的生成逻辑、精神内涵及时代价值

在线全文

学校读者我要写书评

暂无评论

菏泽学院学报 2024年第3期46卷 1-7页

作者：段纪乐李德芳聊城大学马克思主义学院山东聊城252000

冀鲁豫边区红色文化是新民主主义革命时期中国共产党带领边区人民在革命斗争中创造的先进文化,是对马克思主义先进理论、伟大建党精神和中华优秀传统文化的继承与弘扬。冀鲁豫边区军民英勇顽强的革命斗争造就了边区红色文化丰富的精神内... 详细信息

冀鲁豫边区红色文化是新民主主义革命时期中国共产党带领边区人民在革命斗争中创造的先进文化,是对马克思主义先进理论、伟大建党精神和中华优秀传统文化的继承与弘扬。冀鲁豫边区军民英勇顽强的革命斗争造就了边区红色文化丰富的精神内涵,蕴含着党群同心、生死与共的骨肉亲情,不畏艰险、敢闯敢干的革命情怀,民族团结、同仇敌忾的大局意识,不怕牺牲、甘于奉献的英雄气概。冀鲁豫边区红色文化是中国共产党人革命精神的生动写照,为新时代党的群众工作提供了历史借鉴,为地方高校思政教育提供了宝贵资源,也为新时代老区乡村振兴提供了动力源泉。

关键词：冀鲁豫边区红色文化生成逻辑精神内涵时代价值

在线全文

学校读者我要写书评

暂无评论

长江砾石层及其区域对比

华南地质 2024年第3期40卷 528-537页

作者：陈立德邵长生中国地质调查局武汉地质调查中心(中南地质科技创新中心) 湖北武汉430205

长江中下游干支流广泛发育早更新世古砂砾石层堆积,如长江支流发育雅安砾石层、白沙井砾石层,干流沿线则发育宜昌砾石层、阳逻砾石层、九江砾石层、安庆砾石层和雨花台砾石层等“长江砾石层”,这些砾石层的时代均为早更新世而不是中新... 详细信息

长江中下游干支流广泛发育早更新世古砂砾石层堆积,如长江支流发育雅安砾石层、白沙井砾石层,干流沿线则发育宜昌砾石层、阳逻砾石层、九江砾石层、安庆砾石层和雨花台砾石层等“长江砾石层”,这些砾石层的时代均为早更新世而不是中新世或上新世。此外,南京及六合地区广泛发育中新世或上新世有玄武岩夹层的洞玄观组、六合组和黄冈组等含砾砂泥岩。长江砾石层及其与南京地区的中新世/上新世含砾砂泥岩的划分与对比,是长江贯通机制及其时限这一重大科学问题研究的重要基础。

关键词：长江砾石层雨花台砾石层中新世更新世

Effect of Black Plate on Corrosion Resistance of T5 Tinplate

在线全文

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research International 2006年第2期13卷 59-64页

作者： HUANG Xing-qiao li Ning JIANG li-min li de-yu department of Applied Chemistry Harbin Institute of Technology Harbin 150001 Heilongjiang China

The effect of black plate on corrosion resistance of T5 tinplate was studied by glow discharge spectrograph, X-ray diffractometer （XRD）, stress tester, roughness tester and metallographic microscope. The result shows that black plate influences corrosion resistance of T5 tinplate intensely. It also indicates that the increase of content of manganese, phosphorus, silicon and aluminum in black plate would reduce the corrosion resistance of T5 tinplate and the increase of degree of crystal orientation on （200） crystal face, ｜X-Y｜ value （internal stress difference within two orientation）, roughness and exposure degree of iron grain after the same acid wash of black plate would enhance the corrosion resistance of T5 tinplate and the grain number of black plate has small effect on corrosion resistance of T5 tinplate.

关键词： T5 tinplate black plate component crystal orientation internal stress corrosion resistance

CYP2C9和COX-2基因多态性对非甾体类抗炎药治疗强直性脊柱炎临床疗效的影响

在线全文

学校读者我要写书评

暂无评论

颈腰痛杂志 2024年第4期45卷 616-621页

作者：杨鑫皮文杰王利元毕德利李涛李素铠川北医学院临床医学院四川南充637100 重庆市垫江县人民医院骨科重庆408300 重庆医科大学附属第二医院骨科重庆400010

目的探讨细胞色素P450同工酶2C9(CYP2C9)和环氧化酶-2(COX-2)基因多态性对非甾体类抗炎药治疗强直性脊柱炎(AS)临床疗效的影响。方法选择2020年1月至2021年6月在该院就诊的117例AS患者作为观察组;根据“性别相同、年龄±1岁”的原则,选... 详细信息

目的探讨细胞色素P450同工酶2C9(CYP2C9)和环氧化酶-2(COX-2)基因多态性对非甾体类抗炎药治疗强直性脊柱炎(AS)临床疗效的影响。方法选择2020年1月至2021年6月在该院就诊的117例AS患者作为观察组;根据“性别相同、年龄±1岁”的原则,选择同期在该院健康体检的受试者作为117例作为对照组。观察两组受试者CYP2C9*3和COX-2基因启动子区域中的1190A/G和-1195G/A基因多态性,观察AS患者治疗前后的临床资料变化,观察CYP2C9*3、COX-2-1190A/G、COX-2-1195G/A等不同基因型AS患者基于ASAS20改善标准和ASAS40改善标准的疗效是否存在差异。结果两组受试者CYP2C9*3基因型和等位基因频率差异均无统计学意义(P>0.05)。两组受试者COX-2-1290A/G基因型和等位基因频率以及COX-2-1195G/A基因型和等位基因频率的差异均存在统计学意义(P0.05);不同COX-2-1290A/G基因型之间的ASAS20、ASAS40改善情况差异存在统计学意义(P<0.05),其中AA基因型患者的ASAS20和ASAS40改善率均显著高于AG+GG基因型患者(P<0.05);不同COX-2-1195G/A基因型之间的ASAS20、ASAS40改善情况差异存在统计学意义(P<0.05),其中GG+AA基因型的ASAS20和ASAS40改善率显著高于GG患者(P<0.05)。结论COX-2-1290A/G和COX-2-1195G/A多态性可增加AS患者预后不良的风险,可能是预测非甾体类抗炎药治疗AS疗效的生物学指标,而CYP2C9*3多态性与非甾体类抗炎药治疗AS疗效的关系尚有待进一步研究。

关键词：强直性脊柱炎非甾体类抗炎药环氧化酶细胞色素P450同工酶2C9 基因多态性

维普期刊数据库博看期刊

Origin of the Fine Structure of Ultraviolet and Visible Spectra of Silicon Nanocolloids in 2-Propanol

在线全文

学校读者我要写书评

暂无评论

Chinese Physics Letters 1997年第11期14卷 873-875页

作者： ZHU Yong ZHANG li-de Institute of Solid State Physics Chinese Academy of SciencesHefei 230031

The origin of the fine structure of ultraviolet and visible absorption spectra of silicon nanocolloids in 2-propanol prepared in Ar atmosphere by a new sputtering method is *** fine structure is described by phonon-electron coupling in electron transition of *** the basis of the structure model of Si-Si_(4-n)O_(n)(n=0,1,2,3,4),an energy relation has been proposed to explain the fine *** fine structure indicates strong multiple phonon absorption which depends on that how many oxygen atoms the silicon atom bonds to.

关键词： structure phonon absorption

青藏高原隆升对中国疆域自然环境的影响:破解“胡焕庸线”的思考

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

科学技术与工程 2024年第1期24卷 1-33页

作者：滕吉文董庆孟德利马浩刘少华中国科学院地质与地球物理研究所北京100029 中国科学院大学北京100049 吉林大学地球探测科学与技术学院长春180026 可持续发展大数据国际研究中心北京100094 中国科学院空天信息创新研究院北京100094 浙江省微波目标特性测量与遥感重点实验室中科卫星应用德清研究院湖州313200 中国气象科学研究院灾害天气国家重点实验室北京100081 中国21世纪议程管理中心北京100036 中国技术经济学会北京100081

中国疆域广大,人口、土地、耕地和发展程度很不均衡。1935年,知名学者胡焕庸据此提出了著名的“胡焕庸线”。利用这条北东-南西走向直线,将中国大陆划分为东西两个部分。该线的东、西两侧差异悬殊。究其缘由,制约因素多元,而近地表的自... 详细信息

中国疆域广大,人口、土地、耕地和发展程度很不均衡。1935年,知名学者胡焕庸据此提出了著名的“胡焕庸线”。利用这条北东-南西走向直线,将中国大陆划分为东西两个部分。该线的东、西两侧差异悬殊。究其缘由,制约因素多元,而近地表的自然环境和地球内部物质与能量的交换起着重要作用。研究与探索表明:印度次大陆与欧亚大陆两陆-陆板块的碰撞-挤压驱使高原南缘喜马拉雅造山带的突起是根本原因。喜马拉雅造山带的突起阻隔了印度洋南来温湿气流的北进,并形成了西风带,造成了中国西北地域的干旱和荒漠化。在力系作用下,壳、幔物质重新分异、调整,地壳短缩增厚、高原整体抬升不仅导致东、西两部降水量、气温、人口、耕地与生态环境的显著改变,且地球物理场发生了强烈变异与分布不均。西部发展的关键在于水,水进则人进,人进则文化进,文化进则科技进,科技进则发展快,西部人民生活与生存环境不断优化,社会则更安宁。东部不断强化开辟与利用地下空间,西部期盼“红旗河”西部调水工程实施,维护生态环境,兴建亿亩现代化耕地、牧场与绿洲。中国东部与西部共同发展与建设十分重要,饭碗要永远端在自己手中。

关键词： “胡焕庸线” 喜马拉雅造山带突起地壳短缩增厚与高原抬升生态环境 “红旗河”西部调水工程

New design of large fully-steerable radio telescope reflector based on homogenized mesh structure

在线全文

学校读者我要写书评

暂无评论

Research in Astronomy and Astrophysics 2021年第10期21卷 27-36页

作者： li-de Yan Fei Zheng Xi Rui School of Mechano-Electronic Engineering Xidian UniversityXi'an 710071China

The self-weight of a large fully-steerable radio telescope is one of the important factors affecting its *** the existing reflector system scheme,the problem of surface accuracy caused by its large and heavy structure has seriously restricted the application and implementation of large radio ***,a new mesh structure scheme for a large fully-steerable radio telescope reflector is proposed in this *** scheme is based on a homogenized mesh back-up structure in the form of a quasi-geodesic grid and regular quasi-tri-prism or tetrahedron,which can significantly reduce the structural complexity and self-weight of the reflector under the condition that the reflector can meet the desired performance ***,the feasibility and rationality of the scheme are evaluated by numerical simulation analysis,which has significant advantages and provides a new design for the reflector of a large fullysteerable radio telescope.

关键词： telescopes techniques:radar astronomy methods:data analysis

GMM and Misspecification Correction for Misspecified Models with Diverging Number of Parameters

在线全文

学校读者我要写书评

暂无评论

Acta Mathematicae Applicatae Sinica 2019年第4期35卷 780-797页

作者： Qi ZHANG Kai-ping WANG de-li li Lu liN College of Mathematics Qingdao University Qingdao 266071 China School of Management Shandong University Jinan 250100 China department of Mathematics Lakehead University Thunder Bay P7B 5E1 Canada Zhongtai Securities Institute for Financial Studies Shandong University Jinan 250100 China School of Statistics Qufu Normal University Qufu 273165 China

Misspecified models have attracted much attention in some fields such as statistics and econometrics. When a global misspecification exists, even the model contains a large number of parameters and predictors,the misspecification cannot disappear and sometimes it instead goes further away from the true one. Then the inference and correction for such a model are of very importance. In this paper we use the generalized method of moments(GMM) to infer the misspecified model with diverging numbers of parameters and predictors, and to investigate its asymptotic behaviors, such as local and global consistency, and asymptotic normality. Furthermore, we suggest a semiparametric correction to reduce the global misspefication and, consequently, to improve the estimation and enhance the modeling. The theoretical results and the numerical comparisons show that the corrected estimation and fitting are better than the existing ones.

关键词： misspecified model high dimensionality generalized method of moments misspecification correc- tion