秦皇岛市农田杂草的种类与生育期

实地考察了秦皇岛市下辖的三区四县 (北戴河区、山海关区、海港区、昌黎县、抚宁县、卢龙县、青龙县 )农田杂草的种类、分布、危害及主要杂草的生育期。秦皇岛市有农田杂草 5 3科 15 8属 2 4 4种 ,其中恶性杂草 6科 11属 12种 ;寄生性杂草 1科 1属 4种 ;普通性杂草 4 6科 14 1属 2 2 8种。列出了秦皇岛市农田杂草名录。     

黔中不同耕地类型土壤杂草种子库研究

对黔中地区旱地、玉米地、蔬菜地、苗圃地4种不同耕地类型的土壤杂草种子库的种子组成、数量及种子萌发过程和规律进行研究，结果表明：4种不同耕地类型土壤杂草种子库中种子共有35个种，隶属18科33属，且以草本为主，木本仅1种；旱地共有8科12属13个种，优势种为看麦娘，占该类型种子库种子数量的49．1％；玉米地共有16科23属25种，优势种为辣子草，占该类型种子库种子数量的19．6％；蔬菜地共有12科15属17个种，优势种为金色狗尾草，占该类型种子库种子数量的25．9％；苗圃地共有14科18属20个种，优势种为辣子草，占该类型种子库种子数量的34．0％．4种不同耕地土壤类型的杂草种子库种子萌发规律基本一致，均可分成3个阶段，即3月26日以前为萌发初期、3月底到4月上旬为萌发盛期、4月中旬以后为萌发缓慢增长期。     

长白山区居住区绿化植物调查研究

经过2年的调查研究,报道了长白山区居住区共有52科、102属、128种绿化植物.其中主要绿化植物有34科、56属、60种,一、二年生草本19科、37属4、2种,多年生草本13科、28属、33种,草质藤本2科、2属、2种,乔木15科2、1属2、8种,灌木9科、14属、20种,木质藤本2科、3属、3种.针对当前绿化现状中存在的主要问题,对将来住宅区绿化的规划提出了几点对策和建议.     

四川农田维管植物杂草分布区类型初探

在<四川农田常见杂草原色图谱>记载及实地调查的基础上,分析了四川农田常见杂草中维管植物科和属的区系特征.结果表明,四川农田杂草有维管植物81科332属651种(含变种和变型),其中外来入侵杂草48种.科的分布区类型分属5个类型4个变型,属的分布区类型隶属于15个类型11个变型,均以热带亚热带分布为主,温带成分占有一定的比例,体现了本区温暖湿润的亚热带气候为杂草提供了适宜的生长环境,温带成分占有一定的比例,表现出从热带亚热带向温带过渡的性质.世界分布的科属占有较大的比例,这些科属构成了四川农田杂草的主体;热带亚热带起源的植物较易入侵四川.     

燕山地区野生果树种质资源

燕山地区野生果树种质资源丰富,初步查明有野生果树19科、31属、87种,其中乔木6科、10属、27种;灌木12科、17属、49种;木质藤本3科、5属、9种;草本2科、2属、2种。该区不同海拔高度分布着不同的野生果树类型,针对野果资源开发利用现状与存在问题,提出了开发利用建议。     

湖北省黄石市外来入侵植物的调查及研究

通过长期野外调查和文献资料的整理分析,发现黄石市外来入侵植物主要有48种41属21科。其中恶性杂草1种,区域性恶性杂草8种,常见杂草12种。同时本文对黄石市外来植物的入侵途径、危害作用及防治方法也进行了初步探讨。     

湖北省外来入侵植物的初步研究

通过调查和对文献资料的整理和分析,初步确定湖北省外来入侵植物有56种,隶属于20科41属,其中菊科的种类最多,有13种,其次是苋科和蝶形花科,分别有6种、5种．从来源看,有35种来源于美洲,其他种来源于欧洲、亚洲、非洲等地区．人侵植物中有杂草54种。包括2种被列为我国的检疫杂草。即豚草和毒麦．这些外来物种的入侵,特别是一些有毒或恶性杂草的侵入与蔓延．已对省内部分地区产生了许多负面的影响．对其传人途径、主要危害以及防治措施也作了初步的分析。     

麦田杂草消长危害调查与防治技术研究

根据调查统计,在全区境内小麦田中均有杂草分布和危害,共有各类杂草14科29种。阴湿区麦田杂草种类较多,危害最重;其次是川水地;干旱区与一般干旱区较轻。必需采用综合防治技术,才能达到理想的防治效果。     

秦岭地区百合科药用植物资源多样性及其评价

调查研究结果表明，秦岭地区共有百合科药用植物26属69种，分别占本区百合科植物资源总属数的89．7％、总种数的57．0％，其中这些种的生活型以多年生草本为主；药用部位以根状茎类入药的最多，其次是鳞茎类，全草类位居第三；药用功能主要有解表药、清热药、补益药、化痰止咳平喘药和涌吐药等；药用成分主要含生物碱、强心苷及甾体皂苷类、醌类化合物、含硫化合物、多糖等．属、种的地理成分分析表明，属的地理成分以温带成分为主，占本区总属数的92．3％，温带成分中以东亚分布、北温带分布、东亚和北美洲间断分布为主，分别占本区温带分布属数的33．3％、29．2％和19．2％，热带成分仅占本区总属数的7．7％；种的地理成分以中国特有成分和东亚-成分（包括变型）为主，分别占本区总种数的58．0％和20．2％，热带成分仅有热带亚洲一个分布型，占本区总种数的8、7％．对69种药用植物进一步分析的基础上，制定了药用植物评价标准，并提出了保护和利用建议．     

西安地区草坪杂草的种类、危害及其防治

通过对西安地区草坪杂草种类与多度的调查、统计和分析，发现48种草坪杂草，隶属23科，草坪杂草一年生杂草29种，多年生杂草19种，其中禾本科杂草8种，占杂草总数的17％，菊科12种，占杂草总数的25％。提出春季草坪建趔地，为避免杂草危害应以早春种植为宜，对杂草防治应选用适合当地生长的草坪草种为宜等。     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that     

On the Thermodynamic Limit for Responses to Static Electromagnetic Fields

For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the     

Call for Papers

<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with     

Journal of Donghua University ( English Edition) Contents of Volume 31

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