评《周易科学观》对元素周期表的解释

徐道一先生的<周易科学观>一书,据书评者说:“畅论了<周易>和现代自然科学的联系,综合会通了近十年国内外关于<周易>与现代自然科学的关系的各种论著,更提出了自己的独到见解,……可以说是十年来的科学观点研究<周易>的丰富成果的一次总结“.[徐道一1992,序]徐道一先生自己介绍:<周易科学观>的“第三、四、五章用大量、可靠的现代科学资料从天、地、生、数、理、化综合研究等方面来论述<周易>的一些基本概念“.[徐道一1992,前言]他认为:“从根本上看来,<周易>‘尽宇宙之妙,通天人之际‘“.[徐道一1992,2页]他更认为,正确区分东方科学技术的精华和糟粕的问题中,“核心问题之一是对<周易>的评价“.[徐道一1992,239页]……     

《湖泊科学》近10年(2006—2015年)自引及其原因剖析

【目的】 分析《湖泊科学》近10年的自引行为变化规律,剖析产生原因,思考期刊非正常自引现象,引导期刊自引的客观认识,更好地办好学术期刊。【方法】 根据《中国科技期刊引证报告(核心版)》的数据以及《湖泊科学》2006—2015年载文的参考文献,得到《湖泊科学》近10年的自引率(R_SC),总被引频次(F_TC),总自引频次(F_SC),对影响因子(IF)有贡献的总被引频次(F_TCIF)、自引频次(F_SCIF),自引率(R_SCIF),载文数量,平均引文数量以及IF等评价指标,分析各指标的变化趋势以及相互之间的关系。【结果】 在无人为操控的前提下,《湖泊科学》近10年R_SC变化较小,F_TC、F_SC、F_SCIF以及载文数量均有升高趋势,R_SCIF略高于R_SC,但是自引对IF无显著影响。【结论】 R_SC与学科大小和研究范围有关。增加科研投入、提升期刊内容质量、应用数字化手段以及加大推广力度等因素导致了F_TC、F_SC和F_SCIF等指标升高。期刊出现R_SC过高或突然大幅度升高、F_SCIF与IF有很强的相关性、R_SCIF大大高于R_SC等现象时,很可能是人为操控所致。中国科技期刊编辑只有自律自强,才能够使得中国科技期刊的学术质量真正获得国内科技工作者的认同并且在国际舞台上占有一席之地。     

尼采的挑战评戴维·罗宾逊《尼采与后现代主义》

近年来,英国图标书局(IconBooks)出版了一套系列丛书“后现代遭遇“(Postmodern Encounters).这套丛书中的每一册都以一位思想家的某个重要思想为主线,结合当代世界的一个特定文化现象,介绍和探讨所谓的“后现代社会“的特征.该丛书已经出版的分册有20余种,其中包括<乔姆斯基与全球化>、<道金斯与自私基因>、<德里达与历史的终结>、<海德格与纳粹>、<柏拉图与互联网>、<维特根斯坦与心理分析>等.该丛书宣称,它的每一本小册子“讨论一个处在当代思想的风尖浪口上的观念“,整套书是“塑造21世纪的大争论的小导引“.……     

Cu-12(n－1)n和“02(n－1)n”-Cl高温超导系列

本文简要介绍2个铜氧化物高温超导体(HTSC)系列：CuBa₂Ca_n-1Cu_nO_2n+2+δ,即Cu-12(n-1)n, 简称Cu-系;和(Sr,Ca)_n+1Cu_nO_2n(Cl,O)₂, 即“02(n-1)n”Cl,简称Cl-系。2个系列均含有多层［CuO₂］平面,具有高的超导临界转变温度（T_c）。Cu-1234 相的T_c117K,“0212”-Cl的T_c 80K。特别是Cu系具有良好的高温高磁场超导性能。Cu-1212与YBa₂Cu₃O₆晶体同构,加之仅含碱土和铜的氧化物,组份经济,操作安全,Cu-系因此具备诱人的应用开发潜力。与常规的HTSC不同,Cl-系的层间构成是卤化物,而非通常的氧化物。根据这一结构特点用“顶角氧”掺杂实现了“ 0212”Cl的T_c80K的超导转变。研究表明“0212”-Cl具有与全氧化物HTSC可比的超导性能,预示了对卤氧化物高温超导体群研究和开发的乐观前景。     

能源经济学研究前沿 专家视点

全球能源变革呼唤能源经济学创新  （何建坤,清华大学） 能源-环境-经济综合评估模型的发展趋势  （范英 朱磊,中国科学院科技政策与管理科学研究所） 大数据时代的能源金融  （郭剑锋 姬强,中国科学院科技政策与管理科学研究所） 应对能源和气候变化挑战： 政策导向型研究  （王 毅,中国科学院科技政策与管理科学研究所） 构建开放的国际原油交易平台 完善有效的能源市场体系  （褚玦海,上海期货交易所/上海国际能源交易中心） 非常规油气开发在美国的兴起对全球油气市场的影响  （乌米·伊力达尔,美国路易斯安那州立大学能源研究中心、尼日利亚哈科特港大学绿色能源研究所） 能源、市场和市场失灵  （阿多尼斯·雅筑,加拿大多伦多大学经济系）     

中国白花丹科花粉形态研究

The present paper describes the pollen morphology of 30 species belonging to 7 genera of Plumbaginaceae from China.  The pollen grains were all examined under light microscope, and those of some species under scanning and transmission electron microscope.       The pollen grains of the family are subspheroidal, prolate or oblate, (37.5-74.5)× (40.4-81.9)μ in size, 3-colpate, rarely 4-6-colpate,  only pancolpate in  Ceratostigma willmottianum.  The exine 2-layered, 2.0-7.4μ thick, sexine thicker than nexine, verrucate, reticulate or coarsely reticulate.       On the basis of the morphology, two types of pollen grains are distinguished in the family:       (1)  The pollen grains are 3-(rarely 4-6 ) or pancolpate, the exine verrucate. They are found in the tribe Plumbagineae (inculuding the genera Ceratostigma, Plumbago and Plumbagella).       (2)  The pollen grains are all 3-colpate, the exine reticulate or coarsely reticulate. They are found in the tribe Staticeae (including the genera Acantholimon, Ikonnikovia, Goniolimon and Limonium ).     

长三角地区环境库兹涅茨曲线探讨

CO₂减排是绿色发展当然要求。走“绿色发展”是经济与环境友好的必由之路。本文首先探讨长三角的江苏、浙江和上海CO₂排放与经济增长的环境库兹涅茨曲线,发现上海人均CO₂和人均GDP、江苏CO₂和人均GDP、浙江CO₂和GDP存在“∩”型的EKC,根据各自因变量时间序列拟合生长模型,经测算,2012年上海即已出现拐点,2014年浙江出现拐点,江苏于2016年出现拐点。在LMDI分解模型中引入碳源因子,将CO₂排放的驱动因素分为排放结构因子、碳源因子、强度因子、社会富裕因子和人口因子,使用三期移动平均法调整原始数据后进行效应计算,得到社会富裕因子是长三角CO₂排放增加的最主要助推器,人口因子次之。强度因子是长三角CO₂排放的最大抑制性因子,碳源因子是长三角CO₂排放的次要抑制性因子。排放结构因子对CO₂排放增量作用有限的结论,最后提出使用多元结构能源,调整能源消费方向,鼓励消费低CO₂排放能源,加重高CO₂排放能源使用成本,重视节能减排教育和宣传,减缓社会财富、人口因子等发展权引致的CO₂必要性排放等建议,可作为经济发达地区把握CO₂排放现状、制定践行国家和区域CO₂减排政策等参考。     

医学论文中成组t检验P值错误及其原因分析

【目的】 调查医学论文中成组t检验的P值错误,分析错误原因,并提出相应措施。【方法】 选取236种医学期刊,每种期刊选取1项成组t检验,核验其P值,应用χ²检验、Mantel-Haenszel法、二项式logistic回归分析P值错误。【结果】 236项成组t检验中,50项存在P值错误。单因素分析结果显示,核心期刊与非核心期刊相比,P值错误发生率差异具有统计学意义(χ²=4.871,P=0.027);给出具体P值组与未给出具体P值组相比,P值错误发生率差异具有统计学意义(χ²=15.440,P<0.0001)。将是否给出具体P值作为混杂因素,比较核心期刊与非核心期刊P值错误发生率,差异无统计学意义(χ²=2.703,P=0.100)。多因素分析结果显示,是否方差齐(OR值为0.470,95%CI为0.230~0.961)、是否给出具体P值(OR值为5.459,95%CI为2.311~12.895)具有统计学意义。【结论】 医学论文成组t检验P值错误较多。为及时发现P值错误,期刊编辑应当重视对统计学方法应用条件的审查,要求作者给出统计描述以及统计推断的具体结果,能够利用简单易学的统计学软件核实P值。     

商业模式创新的研究热点及其演化可视化分析

针对SCI和SSCI数据库1997-2016年的研究文献,借助CiteSpaceIII和Alluvial flow等软件,通过“文献共被引聚类”、“标志性文献”、“突发文献”和“突现词”等指标开展了商业模式创新的可视化科学计量分析,揭示了20年间商业模式创新的研究热点及演化过程,探究了未来商业模式创新的新趋势。研究发现,商业模式创新的主要热点包括“价值创造”、“开源”和“商业模式挑战”等;热点呈现出由20世纪末期的“信息技术”,21世纪初的“互联网”、“电子商务”和“大规模定制”,发展到目前的“云制造”、“云计算”和“企业社会责任”等演进趋势;AMIT R、TEECE DJ、CHESBROUGH H和VENKATRAMAN N等人的相应研究成果是本领域热点文献;“虚拟现实”、“人工智能”、“3D打印”和“仿真研究”等有可能成为未来的商业模式创新热点。本研究可以促进商业模式创新的理论发展,为学者明确商业模式创新的研究方向,为企业开展商业模式创新提供指引和借鉴。     

引洮供水工程水资源开发利用探讨

引洮供水工程是以九甸峡水利枢纽为龙头,为改善甘肃省中部地区极度缺水现状而实施的跨流域调水工程。2010年和2020年水平年洮河下游总需水量分别为47.26×10⁸m³和47.74×10⁸m³,引洮需水量分别为2.14×10⁸m³和6.04×10⁸m³。在分析九甸峡梯级水库群特点的基础上,以尽可能满足引洮水量、洮河下游生产生活需水,以及下游生态用水为目标,建立了该系统的模拟调度模型,并确定了系统结构和调度原则。结合引洮工程实际情况,设定了三种方案,分别考虑2010年一期工程、2020年一期工程和2020年二期工程。通过长系列模拟计算,得出了各方案的水资源利用情况,模拟计算表明,不同水平年多年平均引洮水量和洮河下游经济社会、生态环境用水均可保证,但冲沙用水不能满足,三个方案缺水量分别为0.95×10⁸m³、0.98×10⁸m³和2.31×10⁸m³;典型年计算结果表明,只有在来水较丰时,才能同时满足洮河下游需水量和引洮水量的需求,典型枯水年和平水年分别缺水11.51×10⁸m³和3.13×10⁸m³。     

期刊影响力指数排名的合理性分析

【目的】 探讨期刊影响力指数的科学合理性及其可能存在的不足,以利于决策者、办刊人以及作者更加科学地评估学术期刊影响力,预测期刊发展潜力。【方法】 以2015—2017年《中国学术期刊影响因子年报》的10个期刊指标数据为研究对象,运用IBM SPSS软件,采用主成分分析法,求得各期刊的综合主成分得分(F),按照F对期刊进行排名;将F与期刊影响力指数(f_CI)排名结果进行对比分析;采用Spearman秩相关系数,比较f_CI和F与10个指标的相关程度。【结果】 F与10个指标的相关性总体高于f_CI;f_CI和F与即年指标的相关系数相对较小,但是F明显高于f_CI。【结论】 F排名更接近各项指标共同表征的期刊水平;更能反映期刊的反应速率和被引强度;在参阅期刊f_CI排名时,应当特别注意参考期刊的即年指标。     

大气14CO2观测：碳排放评估的新方法

我国作为碳排放大国,面临着碳达峰、碳中和（以下简称“双碳”）目标任务和国际碳减排压力。因此,准确的碳排放数据对于评估“双碳”目标和国际履约非常重要。联合国政府间气候变化专门委员会（IPCC）报告推荐将二氧化碳（CO₂）观测与大气反演结合来“自上而下”地校验“自下而上”的碳排放清单,并指出加入大气¹⁴CO₂观测可以更准确地校验碳排放清单。放射性碳同位素（ ¹⁴C）是化石源CO₂最准确的示踪剂,已被国际社会广泛推荐用于碳排放评估。文章基于大气¹⁴CO₂观测的国际发展趋势和国内的紧迫状况,建议加大支持力度,建立大气¹⁴CO₂观测网络;开展培训,统一相关标准,积极参与国际交流;尽快开展¹⁴CO₂观测与大气反演相结合的研究。以此使我国的碳排放研究水平与国际接轨,并提高碳排放数据的可靠性,进而服务国家的“双碳”目标和气候外交谈判。     

半蒴苣苔属的研究(续)

The genus Hemiboea is a curious genus of the tribe Didymocarpeae (Cyrtandroi- deae), characterized by its peculiar pistil with one fertile carpel and its follicle-like capsule. This genus has not yet been thoroughly studied since its establishment by C. B. Clarke in 1888.  In the present paper, the taxonomic history is briefly reviewed; the external morphology, leaf his- tology, pollen morphology and geographical distribution are discussed; a key to the 21 species recognized by the author is provided; and the economic uses reported in various publications are summarized.       I.  Morphology       (1)  Sclereids  The foliar sclereids, occurring in this genus and defined by their forms, fall into two types.       (A) Vermiform selereids  This type of sclereids is noted in 15 species and may be clas- sified into two groups according to their positions in leaf tissues.  Those of the first group are interspersed in the ground tissue around the vascular bundles of leaves and noted in 12 species, i.e.H. longisepala, H. cavaleriei, H. bicornuta, H. fangii, H. omeiensis, H. gracilis, H. glandulosa, H. mollifolia, H. pingbianensis, H. parviflora, H. strigosa and H. gamosepala, and those of the second group are dispersed in the mesophyll, occurring in H. subcapitata, H. henryi and H. latisepala.       (B) Astrosclereids The sclereids of this type are discovered for the first time in Hemiboea, dispersed in the mesophyll of a single species, i.e.H. lungzhouensis.      No foliar sclereids are found in the remaining 5 species, i.e.H. integra, H. flaccida, H. longgangensis, H. subacaulis and H. follicularis.      The differences in forms and positions of the foliar sclereids and their absence or pre- sence are of great help in understanding the relationship between the infrageneric taxa.    (2)  Pollen grains  The pollen grains of 19 species were examined with LM and SEM. They are 3-colporate, subglobose or prolate, 20-38.8×22-28μm.  The exine  is  1.3-2μm thick and the sculpture is foveolate (e.g.H. cavaleriei) to reticulate (e.g.H. omeiensis).  In Sect. Subcapitatae the pollen grains are subglobose or prolate, while those of Sect. Hemiboea are prolate.       No pollen grains are observed in anthers of 13 speciemens of H. subacaulis var. subacaulis and var. jiangxiensis.        (3)  Seed-coat Under SEM the seed-coat exhibits considerable diversity in the genus, fur- nishing useful characters for explaining the relationship between the two sections.       2.  Geographical distribution  The genus Hemiboea ranges from the eastern border of the Xizang Plateau and Yunnan Plateau eastwards to Ryu Kyu Islands, and from the southern slope of the Qinling Range southwards to northern Vietnam.  The karst region of S. E. Yun- nan and W. Guangxi is the centre of maximum variation of the genus and is probably its origin centre, where the most primitive taxon exists, and where more species (13 species, i.e. 61.9 per cent of the sum total) and more endemic species (8 species) are found than elsewhere.       3.  Classification  The genus consists of 21 species and 6 varieties which are classified into 2 sections.  The Clarke's classification is accepted, but emended here as follows:       Sect. 1. Subcapitatae Clarke Sepals free or posterior ones connate.  Muri of the seed-coat laevigate or rugose; bottom of meshes flat, smooth or with few verrucae.  Pollen grains subglo- bose or prolate.       Sect. 2. Hemiboea Sepals connate.  Muri of the seed-coat tuberculate or aliform-tuberculate; bottom of meshes flat or concave, with dense verrucae.   Pollen grains prolate.       Based on the analysis of external and internal morphological characters, the main evolu- tionary trends in the genus are discussed and enumerated, and a hypothesis indicating the re- lationships between the two sections is given.     

徐氏蕨属——中国云南早泥盆世陆地植物的一个新属

  A new psilophytic plant, Hsüa robusta, is found in the Xujiachong Formation  (Emsian) of the Lower Devonian from the Qüjing (= Kütsing) district of Yunnan,  China.  This plant is tentatively referred to the Cooksoniaceae of Rhyniales.       Hsüa gen. nov.       Type species: Hsüa robusta (Li et Cai) C. S. Li.       Diagnosis:  Plants erect and then creeping. Main axes dividing pseudomonopodial- ly and bearing dichotomous lateral branches which somewhat differentiate into vegeta, tire and fertile ones, with dichotomous root-like and rhizophore-like appendages.  Spo- rangia terminal, round to reniform or wide reniform, dehiscing along distal margin into two equal halves.  Spores homosporous, trilete.  Stomata anomocytic.  Protostele cen- trarch.       Hsüia robusta (Li et Cai) C. S. Li, comb. nov.       Cooksonia zhanyiensis Li et Cai, Acta Geologica Sinica, 52 (1) 1978, p. 10, pl. II, fig. 6.——Taeniocrada robusta Li et Cai,ib. p. 10, pl. II, fig. 7—14.       Diagnosis:  Characters same as in generic diagnosis. Main axes 6—10 mm wide and at least 24 cm long, with vascular strands 1.2—2.4 mm acr  oss.  Fertile branches 3—4 times equally or unequally dichotomous, 10—1.5 mm in width and up to 11 cm in length, possessing a vascular bundle of 0.5 mm in its greatest diameter.  Branches circinately coiled in apical regions.  Axial tubercles, root-like and rhizophore— like appendages aris- ing from the main axes usually anterior to the lateral branches. Axial tubercle round with a diameter of 2.2—2.4 mm, having a vascular bundle about l mm across.  Root- like branches 3 times bifurcate, 1—0.3 mm wide and up to 1.5 cm long, with a vascular bundle about 0.1 mm across.  Rhizophore-like appendages forked, 3—1.7 mm in width, possessing a vascular bundle of 0.7 mm in its greatest diameter. Root-like protuberances sometimes arising from rhilzophore-like branches.   Epidermal cells of axes generally elongate, measuring 60—290μby 25—60 μ.  Stomata mainly fusiform, 90—110 μ long and 50—60μ wide, consisting of a pair of guard cells enclosing a pore 6—15μ  in length and 1—3μ  in width.  Cuticle of guard cells quite thick.  Stomatal density about 5 per mm2.  Sporangia 0.8—4.2 mm high, 1.0—8.2 mm across, usually having a dehiscent distal border which measures 50—100μ broad.  Demarcation between sporangium and its stalk quite clear.  Epidermal cells of basal part of sporangial walls elongate, about 100 μ long and 30μ wide, but those of distal part isodiametrally polygonal, about 50μ in diame- ter.  Stomata, radially arranged scattering over sporangial walls, generally round about 50μ in diameter and 50 per sporangium.  Spores round, 18—36μ (average 27μ) indiameter, and smooth.  Tracheids of protoxylem about 10μ across; those of metaxylem about 30μ across, with scalariform thickening.      This plant is similar to Renalia hueberi Gensel in general morphology, but differs from the latter in possessing root-like and rhizophore-like branches.      The generic name is derived from Prof.  Hsü Jen.     This paper is a thesis for M. Sc.     

中国梅花衣属的初步研究

 Parmelia is a genus of economical importance.   According  what  was  recorded, Meyen & Flotow were the first foreigners to study Chinese lichens in 1843.  Up to the present time 74 species, 24 varieties and 11 forms have been described from China.      The majority of specimens reported in this paper were collected by many Chinese botanists and collectors from 21 provinces from 1928--1962, while a few of them were collected by Licent from 1916 to 1917 and by Poliansky in 1957.      The system of classification adopted here is that held by A. Zahlbruckner in 1926. But in section Hypotrachyna, the two subsections-Myelochroa and Myeloleuca proposed by Asahina are adopted and Parmelia xanthocarpa which has not been properly placed before, is here referred to the subsection Myelochroa.      In the subgenus Hypogymnia the writer discovers that the length of spores of two species are longer than 10μ, especially  Parmelia macrospora reaches  17.5μ long.  So far as the writer knows, the upper limitation of the spore length  recognized  by  many lichenologists has been 10μ in this subgenus.  The spore measurement of this subgenus needs, therefore, to be revised in future.       In this paper 78 species, 14 varieties and 6 forms are presented.  Among them, 5 species, 5 varieties and 1 forms are considered as new and two new combinations have been made.  Out of all these, 31 species, 6 varieties and 2 forms are first recorded from China.  All the materials cited are deposited in the Mycological Herbarium of Instituteof Microbiology, Academia Sinica, Peking.     

天津北三河水系雨洪水资源潜力的估算及其应用

基于资源水利的理念,以雨洪水资源为研究对象,针对其动态性分别引入理论潜力、可实现潜力、现实潜力及待开发潜力的概念及算法。以天津北三河水系为典型区域,分别计算了各流域和整个水系的各个频率年的自产水量、理论潜力、可实现潜力,给出了各频率来水情况下雨洪水资源潜力的年内分配过程,并以待开发潜力为主要关注对象,对其进行频率分析,计算得到50%、20%、10%、5%各频率年下的待开发潜力值依次为4.42×10⁸m³、12.96×10⁸m³、20.02×10⁸m³、27.35×10⁸m³,为以后的雨洪水资源利用模式的制定提供了依据。     

区位基尼系数与中国工业企业R&amp;D资源地区差异研究

本文借鉴相关研究成果,首次将基尼系数分析方法引入工业企业R&amp;D资源地区差异研究之中,在对我国工业企业R&amp;D资源分布综合分析的基础上,计算了2000年我国工业企业R&amp;D资源地区分布的区位基尼系数,用以分析各地区工业企业R&amp;D资源分布情况.     

磁制冷材料研究中的物理问题

提出并讨论了当前磁制冷材料研究中出现的一些相关物理问题,其中 包括：在Gd₃Ga_5-XFe_XO₁₂中由于巨自旋团簇的形成而导致的有效制冷温度范围的改变,Gd₃Ga₅O₁₂中的磁化强度以及比热的模型计算,在磁热效应计算中Maxwell关系以及磁Clausius-Clapeyron方程的应用,以及重-轻稀土合金中的磁有序性质等。     

论胡桃科植物的地理分布

 The present paper aims to discuss the geog raphical distribution of the Juglandaceae on the basis of unity of the phylogeny and the process of dispersal in the plants.       The paper is divided into the following three parts:       1.  The systematic positions and the distribution patterns of nine living genera in the family Juglandaceae (namely, Engelhardia, Oreomunnea, Alfaroa, Pterocarya, Cyclo- carya, Juglans, Carya, Annamocarya and Platycarya) are briefly discussed.  The evolu- tional relationships between the different genera of the Juglandaceae are elucidated. The fossil distribution and the geological date of the plant groups are reviewed.  Through the analysis for the geographical distribution of the Juglandaceous genera, the distribu- tion patterns may be divided as follows:       A.  The tropical distribution pattern       a. The genera of tropical Asia distribution: Engelhardia, Annamocarya.       b. The genera of tropical Central America distribution: Oreomunnea, Alfaroa.       B.  The temperate distribution pattern       c. The genus of disjunct distribution between Western Asia and Eastern Asia: Pterocarya.       d. The genus of disjunct distribution between Eurasia and America: Juglans.      e. The genus of disjunct distribution between Eastern Asia and North America: Carya.      f. The genera whose distribution is confined to Eastern Asia: Cyclocarya, Platy- carya.      2.  The distribution of species      According to Takhtajan’s view point of phytochoria, the number of species in every region are counted.  It has shown clearily that the Eastern Asian Region and the Coti- nental South-east Asian Region are most abundant in number of genera and species. Of the 71 living species, 53 are regional endemic elements, namely 74.6% of the total species. The author is of the opinion that most endemic species in Eurasia are of old endemic nature and in America of new endimic nature.  There are now 7 genera and 28 species in China, whose south-western and central parts are most abundant in species, with Pro- vince Yunnan being richest in genera and species.      3.  Discussions of the distribution patterns of the Juglandaceae A.       The centre of floristic region B.         The centre of floristic regions is determined by the following two principles:  a. A large number of species concentrate in a district, namely the centre of the majority; b.  Species of a district can reflect the main stages of the systematic evolution of the Juglandaceae, namely the centre of diversity.  It has shown clearly that the southern part of Eastern Asian region and the northern part of Continental South-east Asian Region (i.c. Southern China and Northern Indo-China) are the main distribution centre of the Juglandaceae, while the southern part of Sonora Region and Caribbean Region  (i.c. South-western U.S.A., Mexico and Central America) are the secondary distribution centre.       As far as fossil records goes, it has shown that in Tertiary period the Juglanda- ceae were widely distributed in northern Eurasia and North America, growing not only in Europe and the Caucasus but also as far as in Greenland and Alaska.  It may be considered that the Juglandaceae might be originated from Laurasia.  According to the analysis of distribution pattern for living primitive genus, for example, Engelhar- dia, South-western China and Northern Indo-China may be the birthplace of the most primitive Juglandaceous plants.  It also can be seen that the primitive genera and the primitive sections of every genus in the Juglandaceae have mostly distributed in the tropics or subtropics. At the same time, according to the analysis of morphological cha- racters, such as naked buds in the primitive taxa of this family, it is considered that this character has relationship with the living conditions of their ancestors.  All the evidence seems to show that the Juglandaceae are of forest origin in the tropical moun- tains having seasonal drying period.       B.  The time of the origin       The geological times of fossil records are analyzed. It is concluded that the origin of the Juglandaceae dates back at least as early as the Cretaceous period.       C.  The routes of despersal       After the emergence of the Juglandaceous plant on earth, it had first developed and dispersed in Southern China and Indo-China.  Under conditions of the stable tempera- ture and humidity in North Hemisphere during the period of its origin and development, the Juglandaceous plants had rapidly developed and distributed in Eurasia and dis- persed to North America by two routes: Europe-Greenland-North  America  route  and Asia-Bering Land-bridge-North America route.  From Central America it later reached South America.      D.  The formaation of the modern distribution pattern and reasons for this forma- tion.      According to the fossil records, the formation of two disjunct areas was not due to the origin of synchronous development, nor to the parallel evolution in the two con- tinents of Eurasia and America, nor can it be interpreted as due to result of transmis- sive function.  The modern distribution pattern has developed as a result of the tectonic movement and of the climatic change after the Tertiary period.  Because of the con- tinental drift, the Eurasian Continent was separated from the North American Conti- nent, it had formed a disjunction between Eurasia and North America. Especially, under the glaciation during the Late Tertiary and Quaternary Periods, the continents in Eu- rasia and North America were covered by ice sheet with the exception of “plant refuges”, most plants in the area were destroyed, but the southern part of Eastern Asia remained practically intact and most of the plants including the Juglandaceae were preserved from destruction by ice and thence became a main centre of survival in the North Hemisphere, likewise, there is another centre of survival in the same latitude in North America and Central America.      E.  Finally, the probable evolutionary relationships of the genera of the Juglanda-ceae is presented by the dendrogram in the text.