PVP接枝PHBV的研究(英文)

采用正交实验设计优化聚乙烯吡咯烷酮(PVP)与聚羟基戊酸-co-羟基丁酸共聚酯(PHBV)在氯苯溶液中的接枝反应工艺。结果表明:乙烯基吡咯烷酮(NVP)与过氧化二苯甲酰(BPO)用量,反应温度显著影响接枝率(GR%)。在优化的反应工艺条件下,接枝率的置信度为90%的置信区间是(9.83±1.14)%,该值与实验结果(10.48%)一致。     

聚乳酸接枝乙烯基吡咯烷酮的初步研究

为改善聚（D,L－乳酸）（PDLLA）的亲水性,以过氧化二苯甲酰为引发剂,四氢呋喃为溶剂,进行了PDLLA接枝乙烯基吡咯烷酮（VP）的试验。IR和^1H NMR测试结果表明：PDLLA可与VP实现接枝反应,摩尔接枝率为1．0％－1．6％。与PDLLA相比,接枝产物的[η]值下降,但吸水率增加、接触角变小,亲水性有所改善。     

苎麻纤维化学接枝改性的研究

以高锰酸钾（KMnO4）为引发剂、甲基丙烯酸甲酯（MMA）为单体，苎麻纤维进行接枝共聚反应。讨论了接枝率与高锰酸钾溶液浓度、预处理温度、预处理时间、硫酸浓度、甲基丙烯酸甲酯浓度、接枝反应温度以及接枝反应时间的关系。结果表明，苎麻纤维的接枝率可达142．4％。     

THESYNTHESIS AND CHARACTERIZATION OF CROSSLINKED GELATIN WITH HYDROPHILIC/ HYDROPHOBIC GRAFTS

以过硫酸钾（ＫＰＳ）－亚硫酸氢钠（ＮａＢＳ）为引发体系，甲基丙烯酸甲酯（ＭＭＡ）及甲基丙烯酸（ＭＡＡ）为接枝单体，制得了具有亲水性与疏水性接枝支链交联明胶．用红外光谱确证了产物结构．实验结果表明，当［ＫＰＳ］＝［ＮａＢＳ］＝６×１０－３Ｍ，［ＭＭＡ］＝６×１０－１Ｍ，Ｇｅｌｘ－ｇ－ＰＭＡＡ＝４ｇ，ＳＬ＝４１００，６０℃反应５小时，接枝率Ｇ％及接枝效率Ｅ％均出现最大值．研究了此类两亲性接枝交联明胶的溶胀行为．     

HDPE固相接枝丙烯酸的研究

以过氧化苯甲酰（ＢＰＯ）为引发剂、二甲苯为界面剂，研究丙烯酸（ＡＡ）在粉料高密度聚乙烯（ＨＤＰＥ）上的固相接枝反应．红外光谱证实了该接枝反应。Ｘ光衍射发现接枝后的ＨＤＰＥ结晶度下降不多，表明接核反应发生在ＨＤＰＥ的无定区域和晶区表面或晶区缺陷上。实验还发现，随着引发剂用量、ＨＤＰＥ颗粒度的增加，反应温度的升高，单体／聚合物比增加，接枝率提高。本研究制得的ＨＤＰＥ—ｇ—ＡＡ，其接枝率可高达１５．９２％。     

氯化聚乙烯接枝水溶性单体

采用溶胀悬浮接枝共聚法,将水溶性单体丙烯酸（AA）、丙烯酰胺（AM）接枝到疏水性氯化聚乙烯（CPE）大分子链上,合成双亲性接枝共聚物。通过正交实验法探讨了反应条件（膨胀剂、单体、引发剂和分散剂用量以及反应时间、反应温度和分散介质用量）对接枝率及接枝效率的影响规律,并用傅立叶红外光谱对接枝物进行了表征。研究结果表明,采用水作分散介质,乙酸乙醋作膨胀剂的溶胀悬浮接枝体第。在回流温度和一定搅拌速度下,可实现CPE接枝水溶性单体AA、AM且接枝（效）率较高。最佳反应条件分别为：CPE－g-AA接枝体系：CPE／AA／BPO／EA／H2O＝2／2／0．65／5／50（g/g/g/mL/mL),反应温度80℃;CPE－g-AM接枝体系：CPE／AM／BPO／EA／H2O＝2／2／0．07／8／50（g/g/g/mL/mL),反应温度72℃。反应时间均为3h。     

丙烯酸固相接枝聚丙烯研究

利用固相接枝共聚的方法，制备聚丙烯接枝丙烯酸（ＰＰ－ｇ－ＡＡ）共聚物。讨论了反应时间、反应温度、单体浓度、引发剂浓度、界面剂等对接枝率的影响。结果表明：聚丙烯固相接枝丙烯酸容易实现，接枝率可达５．８％，接枝物用红外光谱进行表征。ＰＰ－ｇ－ＡＡ可明显改善ＰＰ－ＣａＣＯ３复合材料的界面相容性及力学性能。     

纤维素接枝聚合反应的研究

用高锰酸钾为引发剂，将纤维与丙烯酸进行接枝聚合，研究接枝聚合反应工艺条件对接率的影响。结果表明：高锰酸钾浓度，预处理温度和时间，硫酸浓度，丙烯酸浓度，反应温度和时间均与接枝率有关；反庆中选择高锰酸浓度0.003mol/L，预处理温度60℃和时间10min，硫酸浓度0.2mol/L，丙烯酸浓度2mol/L，反应温度60℃和时间5h，纤维素接率可达35％。     

铈盐引发丙烯酰胺在棉纤维上接枝共聚合反应的研究

采用铈（Ⅳ）盐－棉氧化还原体系引发丙烯酰胺在天然纤维素纤维上接枝共聚，探讨了酸预处理和接枝反应条件对产物平衡接枝率的影响及接枝共聚机理．ＩＲ表征产物具有预期的结构     

聚烯烃熔融挤出接枝马来酸酐的研究进展

对聚烯烃（聚乙烯和聚丙烯）进行马来酸酐单体接枝改性是拓宽聚烯烃使用范围的重要手段．文章对聚烯烃熔融接枝马来酸酐的反应机理、接枝率的影响因素以及提高接枝率的方法进行了综述,并展望了聚烯烃熔融挤出接枝马来酸酐的发展趋势．     

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.     

Design and analysis of generic LBS application developing platform

Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.     

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