种植密度对冀东地区晚播冬小麦籽粒灌浆特性和产量的影响

为探讨不同种植密度下晚播冬小麦的籽粒灌浆特性,分析种植密度与籽粒灌浆参数的关系,于2018～2019年度在河北科技师范学院生命科技实验站进行大田试验.选用京花11号作为试验材料,设525万株/hm2,675万株/hm2和825万株/hm2等3个密度水平,对冬小麦的籽粒灌浆过程用Logistic方程进行拟合,研究小麦籽粒...     

蓖麻高含油率优质栽培模式研究

以密度、氮素、磷素、钾素为参试因子,采用二次回归正交旋转组合设计,对蓖麻杂交新品种含油率综合农艺措施进行研究.结果表明,主要农艺措施对蓖麻含油率增减作用的大小依次为：氮素>钾素>磷素>密度.在相同或相似条件下蓖麻含油率大于50.63%的最佳实施方案为：种植密度以22302～24498株/hm2为适宜,氮素（纯N）122.76～147.96kg/hm2,磷素（P2O5）171.97～196.42kg/hm2,钾素（K2O）158.62～182.77kg/hm2为佳.     

长白落叶松人工林密度表的编制及应用

采用不同林龄长白落叶松人工林的60株优势木数据建立林分饱和密度模型,编制了经营密度表,再利用26块密度近似于合理经营密度的不同生长阶段样地的平均胸径增长量、径阶分布和总蓄积量的分析,评价以经营密度表指导抚育间伐的过程及效果。结果表明:随平均胸径的增大林分密度不断减少,方程N=3 847.345 1e-0.082D适用于预估林分密度,编制的经营密度表反映了0.6～0.8郁闭度下长白落叶松各个生长阶段的最适林分密度。26块模拟样地的间伐前密度为2 883株/hm2,经历3次间伐后的林分平均密度分别为2 000、1 400和1 000株/hm2,最终成熟林的平均林分密度为600株/hm2,树冠竞争因子为416.33,总蓄积量为242.12 m3/hm2,大径材比率达59.26%。     

糯玉米苏玉(糯)1号叶片生长规律的研究

对 6 0万株 /hm2 和 7.5万株 /hm2 密度下的糯玉米苏玉 (糯 ) 1号叶片和植株生长特点、叶片功能期、叶面积和叶片光合势的动态变化进行了试验研究。结果表明 :两种密度下的出叶速度相近 ,各叶出叶速度大小依次是基部三叶 >顶部 >中上部 >中下部。穗叶组叶片生长速度较快 ,叶面积较大 ,其中第 1 6叶 (非穗位叶 )生长速度最快 ,1 5叶叶面积最大。高密度下叶长、叶宽都较小 ,两种密度下最宽叶是最长叶 (穗位叶 )以上二片叶即 1 5叶。高密度下叶面积和光合势较低 ,但高密度的中期稳定 ,后期下降平稳 ;叶面积指数在抽雄吐丝期最高 ,光合势在后期分配比例占 2 /3。植株生长的曲线符合Logistic方程 ,7.5万株 /hm2 比 6 0万株 /hm2密度下的株高低 ,群体株高整齐度也小 ,而产量高 493 .6kg/hm2 。试验表明 :7.5万株 /hm2 相对 6 0万株 /hm2 密度较适合于苏玉 (糯 ) 1号的生长。     

毛竹造林密度调查分析

经上张乡、双庙乡、朱溪镇、下各镇13个行政村21块山地毛竹造林密度调查,调查显示造林密度最高的只有375株/hm2,最低的不足150株/hm2,大多数造林密度在180-210株/hm2。分析认为：毛竹造林密度确定应根据当地母竹资源、劳动力、资金等方面综合考虑,一般毛竹用材林造林按国家、省级规定的下限密度为好,即300-350株/hm2。只要采用合理的肥培管理技术,同样可缩短培育周期,亦可起到节约造林费用,达到事半功倍之效。     

云南松人工林土壤有机碳研究

对云南松人工林土壤有机碳的研究结果表明:云南松人工林土壤1m深范围内碳含量为59.49 g/kg、平均碳密度为163.73 t/hm2。不同土层的碳含量、土壤各层平均10cm有机碳密度排序均为0cm~20cm层20cm~40cm层40cm~60cm层60cm~100cm层,坡度≤25°的土壤碳含量、土壤碳密度均大于坡度25°,阴坡土壤碳含量、土壤碳密度均大于阳坡,不同林分密度的土壤碳含量、土壤碳密度排序均为800株/hm2800株/hm2~1100株/hm21100株/hm2。     

吉林西部盐碱化泡沼和苇塘湿地渔业开发技术

2002～2008年,在半干旱地区的吉林西部大安市进行盐碱化泡沼和苇塘湿地农业综合开发试验示范。采用湿地生态工程、水环境改良以及合理的养殖结构等措施,开发盐碱化泡沼养鱼762hm2,成鱼净产量240～490kg/hm2,平均334.7kg/hm2;纯效益625～1420元/hm2,平均968.2元/hm2;投入产出比1.81～2.97,平均2.20。开发苇塘养鱼1439hm2,成鱼净产量290～430kg/hm2,平均338.3kg/hm2;纯效益497～1417元/hm2,平均794.8元/hm2,投入产出比1.58～3.36,平均2.27。结果表明,采取适当的技术措施,在半干旱的吉林西部开发盐碱化泡沼和苇塘湿地发展淡水养殖是可行的。     

甜糯玉米优质高产配套栽培模式的示范推广

用＂两精四适宜＂即铺膜精细播种、精细管理;适宜播种期、适宜密度、适宜采收期、适宜绿色病虫害防治的综合集成栽培技术,种植迪糯278、京科糯2000、迪甜6号、迪甜10号、鲜糯1号5个甜糯玉米品种,两年来种植推广面积达1966.667hm2,平均增产2550kg/hm2,平均增收4500元/hm2以上,新增经济效益1068万元。     

萌芽更新与植苗更新对尾巨桉人工林收获的影响

应用相对生长法和样方收获法对萌芽更新和植苗更新尾巨桉人工林生物量及生产力进行研究.结果表明:相同密度条件下,植苗更新尾巨桉人工林生物量高于萌芽更新人工林;当密度为1097株/hm2时,植苗更新和萌芽更新尾巨桉人工林的生物量分别为79.193 t/hm2和68.682 t/hm2,年平均净生产量分别为23.998 t/hm2和21.463 t/hm2.植苗更新和萌芽更新人工林群落净生产量排序由高到低依次为:乔木层、枯枝落叶层、灌木层、草本层.萌芽更新尾巨桉人工林生物量随保留密度的增加而增加.不同更新模式尾巨桉林分干材、干皮、枝、叶、根系的生物量分别占总生物量的60.50%～60.86%、5.62%～5.89%、10.88%～11.23%、4.11%～4.54%和18.1%～18.27%.林分生物量分配的大小排序为:干材、根系、枝、干皮、叶.     

播期和种植密度对小麦基部节间性状与抗倒指数的影响

为分析播期和密度对小麦茎秆抗倒能力的调控效应,本试验以华成3366为材料,设置正常播期和晚播两个播期处理,各播期下分别设置225万株/hm2、375万株/hm2、525万株/hm23个种植密度,研究了播期和密度及其互作对小麦产量、株高及基部节间形态学指标、力学特征、化学成分、解剖结构的影响,以明确播期和密度对小麦茎秆抗...     

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.     

An Analysis of Catherine＇s Character——Wuthering Heights

Wuthering Heights, Emily Bronte＇s only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.     

Lower Paleozoic oil relationships within Williston Basin, Canada

The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.     

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